windows: errnoErr(): return ENOENT to reduce code duplication

Change-Id: I51c08a4add9c2b31c4bb7c4421dde227b4fff489
GitHub-Last-Rev: ef8ef8646ca90df893bee4cc8d7879dc1a80ebe4
GitHub-Pull-Request: golang/sys#89
Reviewed-on: https://go-review.googlesource.com/c/sys/+/259537
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Trust: Alex Brainman <alex.brainman@gmail.com>
diff --git a/windows/mkwinsyscall/mkwinsyscall.go b/windows/mkwinsyscall/mkwinsyscall.go
index 910556e..63b905d 100644
--- a/windows/mkwinsyscall/mkwinsyscall.go
+++ b/windows/mkwinsyscall/mkwinsyscall.go
@@ -303,17 +303,13 @@
 
 func (r *Rets) useLongHandleErrorCode(retvar string) string {
 	const code = `if %s {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = %sEINVAL
-		}
+		err = errnoErr(e1)
 	}`
 	cond := retvar + " == 0"
 	if r.FailCond != "" {
 		cond = strings.Replace(r.FailCond, "failretval", retvar, 1)
 	}
-	return fmt.Sprintf(code, cond, syscalldot())
+	return fmt.Sprintf(code, cond)
 }
 
 // SetErrorCode returns source code that sets return parameters.
@@ -867,7 +863,7 @@
 func errnoErr(e {{syscalldot}}Errno) error {
 	switch e {
 	case 0:
-		return nil
+		return {{syscalldot}}EINVAL
 	case errnoERROR_IO_PENDING:
 		return errERROR_IO_PENDING
 	}
diff --git a/windows/syscall_windows.go b/windows/syscall_windows.go
index 65ca6d2..bbd075d 100644
--- a/windows/syscall_windows.go
+++ b/windows/syscall_windows.go
@@ -390,11 +390,7 @@
 	r0, _, e1 := syscall.Syscall(procGetProcAddress.Addr(), 2, uintptr(module), ordinal, 0)
 	proc = uintptr(r0)
 	if proc == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1091,11 +1087,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(sendRecvMsgFunc.sendAddr, 6, uintptr(fd), uintptr(unsafe.Pointer(msg)), uintptr(flags), uintptr(unsafe.Pointer(bytesSent)), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(croutine)))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return err
 }
@@ -1107,11 +1099,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(sendRecvMsgFunc.recvAddr, 5, uintptr(fd), uintptr(unsafe.Pointer(msg)), uintptr(unsafe.Pointer(bytesReceived)), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(croutine)), 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return err
 }
diff --git a/windows/zsyscall_windows.go b/windows/zsyscall_windows.go
index 9c048fd..17133e6 100644
--- a/windows/zsyscall_windows.go
+++ b/windows/zsyscall_windows.go
@@ -24,7 +24,7 @@
 func errnoErr(e syscall.Errno) error {
 	switch e {
 	case 0:
-		return nil
+		return syscall.EINVAL
 	case errnoERROR_IO_PENDING:
 		return errERROR_IO_PENDING
 	}
@@ -365,11 +365,7 @@
 	r0, _, e1 := syscall.Syscall(procRegisterEventSourceW.Addr(), 2, uintptr(unsafe.Pointer(uncServerName)), uintptr(unsafe.Pointer(sourceName)), 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -377,11 +373,7 @@
 func DeregisterEventSource(handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procDeregisterEventSource.Addr(), 1, uintptr(handle), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -389,11 +381,7 @@
 func ReportEvent(log Handle, etype uint16, category uint16, eventId uint32, usrSId uintptr, numStrings uint16, dataSize uint32, strings **uint16, rawData *byte) (err error) {
 	r1, _, e1 := syscall.Syscall9(procReportEventW.Addr(), 9, uintptr(log), uintptr(etype), uintptr(category), uintptr(eventId), uintptr(usrSId), uintptr(numStrings), uintptr(dataSize), uintptr(unsafe.Pointer(strings)), uintptr(unsafe.Pointer(rawData)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -402,11 +390,7 @@
 	r0, _, e1 := syscall.Syscall(procOpenSCManagerW.Addr(), 3, uintptr(unsafe.Pointer(machineName)), uintptr(unsafe.Pointer(databaseName)), uintptr(access))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -414,11 +398,7 @@
 func CloseServiceHandle(handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procCloseServiceHandle.Addr(), 1, uintptr(handle), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -427,11 +407,7 @@
 	r0, _, e1 := syscall.Syscall15(procCreateServiceW.Addr(), 13, uintptr(mgr), uintptr(unsafe.Pointer(serviceName)), uintptr(unsafe.Pointer(displayName)), uintptr(access), uintptr(srvType), uintptr(startType), uintptr(errCtl), uintptr(unsafe.Pointer(pathName)), uintptr(unsafe.Pointer(loadOrderGroup)), uintptr(unsafe.Pointer(tagId)), uintptr(unsafe.Pointer(dependencies)), uintptr(unsafe.Pointer(serviceStartName)), uintptr(unsafe.Pointer(password)), 0, 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -440,11 +416,7 @@
 	r0, _, e1 := syscall.Syscall(procOpenServiceW.Addr(), 3, uintptr(mgr), uintptr(unsafe.Pointer(serviceName)), uintptr(access))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -452,11 +424,7 @@
 func DeleteService(service Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procDeleteService.Addr(), 1, uintptr(service), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -464,11 +432,7 @@
 func StartService(service Handle, numArgs uint32, argVectors **uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procStartServiceW.Addr(), 3, uintptr(service), uintptr(numArgs), uintptr(unsafe.Pointer(argVectors)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -476,11 +440,7 @@
 func QueryServiceStatus(service Handle, status *SERVICE_STATUS) (err error) {
 	r1, _, e1 := syscall.Syscall(procQueryServiceStatus.Addr(), 2, uintptr(service), uintptr(unsafe.Pointer(status)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -488,11 +448,7 @@
 func QueryServiceLockStatus(mgr Handle, lockStatus *QUERY_SERVICE_LOCK_STATUS, bufSize uint32, bytesNeeded *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procQueryServiceLockStatusW.Addr(), 4, uintptr(mgr), uintptr(unsafe.Pointer(lockStatus)), uintptr(bufSize), uintptr(unsafe.Pointer(bytesNeeded)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -500,11 +456,7 @@
 func ControlService(service Handle, control uint32, status *SERVICE_STATUS) (err error) {
 	r1, _, e1 := syscall.Syscall(procControlService.Addr(), 3, uintptr(service), uintptr(control), uintptr(unsafe.Pointer(status)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -512,11 +464,7 @@
 func StartServiceCtrlDispatcher(serviceTable *SERVICE_TABLE_ENTRY) (err error) {
 	r1, _, e1 := syscall.Syscall(procStartServiceCtrlDispatcherW.Addr(), 1, uintptr(unsafe.Pointer(serviceTable)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -524,11 +472,7 @@
 func SetServiceStatus(service Handle, serviceStatus *SERVICE_STATUS) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetServiceStatus.Addr(), 2, uintptr(service), uintptr(unsafe.Pointer(serviceStatus)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -536,11 +480,7 @@
 func ChangeServiceConfig(service Handle, serviceType uint32, startType uint32, errorControl uint32, binaryPathName *uint16, loadOrderGroup *uint16, tagId *uint32, dependencies *uint16, serviceStartName *uint16, password *uint16, displayName *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall12(procChangeServiceConfigW.Addr(), 11, uintptr(service), uintptr(serviceType), uintptr(startType), uintptr(errorControl), uintptr(unsafe.Pointer(binaryPathName)), uintptr(unsafe.Pointer(loadOrderGroup)), uintptr(unsafe.Pointer(tagId)), uintptr(unsafe.Pointer(dependencies)), uintptr(unsafe.Pointer(serviceStartName)), uintptr(unsafe.Pointer(password)), uintptr(unsafe.Pointer(displayName)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -548,11 +488,7 @@
 func QueryServiceConfig(service Handle, serviceConfig *QUERY_SERVICE_CONFIG, bufSize uint32, bytesNeeded *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procQueryServiceConfigW.Addr(), 4, uintptr(service), uintptr(unsafe.Pointer(serviceConfig)), uintptr(bufSize), uintptr(unsafe.Pointer(bytesNeeded)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -560,11 +496,7 @@
 func ChangeServiceConfig2(service Handle, infoLevel uint32, info *byte) (err error) {
 	r1, _, e1 := syscall.Syscall(procChangeServiceConfig2W.Addr(), 3, uintptr(service), uintptr(infoLevel), uintptr(unsafe.Pointer(info)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -572,11 +504,7 @@
 func QueryServiceConfig2(service Handle, infoLevel uint32, buff *byte, buffSize uint32, bytesNeeded *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procQueryServiceConfig2W.Addr(), 5, uintptr(service), uintptr(infoLevel), uintptr(unsafe.Pointer(buff)), uintptr(buffSize), uintptr(unsafe.Pointer(bytesNeeded)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -584,11 +512,7 @@
 func EnumServicesStatusEx(mgr Handle, infoLevel uint32, serviceType uint32, serviceState uint32, services *byte, bufSize uint32, bytesNeeded *uint32, servicesReturned *uint32, resumeHandle *uint32, groupName *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall12(procEnumServicesStatusExW.Addr(), 10, uintptr(mgr), uintptr(infoLevel), uintptr(serviceType), uintptr(serviceState), uintptr(unsafe.Pointer(services)), uintptr(bufSize), uintptr(unsafe.Pointer(bytesNeeded)), uintptr(unsafe.Pointer(servicesReturned)), uintptr(unsafe.Pointer(resumeHandle)), uintptr(unsafe.Pointer(groupName)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -596,11 +520,7 @@
 func QueryServiceStatusEx(service Handle, infoLevel uint32, buff *byte, buffSize uint32, bytesNeeded *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procQueryServiceStatusEx.Addr(), 5, uintptr(service), uintptr(infoLevel), uintptr(unsafe.Pointer(buff)), uintptr(buffSize), uintptr(unsafe.Pointer(bytesNeeded)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -634,11 +554,7 @@
 	r0, _, e1 := syscall.Syscall(procLoadLibraryW.Addr(), 1, uintptr(unsafe.Pointer(libname)), 0, 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -656,11 +572,7 @@
 	r0, _, e1 := syscall.Syscall(procLoadLibraryExW.Addr(), 3, uintptr(unsafe.Pointer(libname)), uintptr(zero), uintptr(flags))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -668,11 +580,7 @@
 func FreeLibrary(handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procFreeLibrary.Addr(), 1, uintptr(handle), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -690,11 +598,7 @@
 	r0, _, e1 := syscall.Syscall(procGetProcAddress.Addr(), 2, uintptr(module), uintptr(unsafe.Pointer(procname)), 0)
 	proc = uintptr(r0)
 	if proc == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -703,11 +607,7 @@
 	r0, _, e1 := syscall.Syscall(procGetModuleFileNameW.Addr(), 3, uintptr(module), uintptr(unsafe.Pointer(filename)), uintptr(size))
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -715,11 +615,7 @@
 func GetModuleHandleEx(flags uint32, moduleName *uint16, module *Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetModuleHandleExW.Addr(), 3, uintptr(flags), uintptr(unsafe.Pointer(moduleName)), uintptr(unsafe.Pointer(module)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -728,11 +624,7 @@
 	r0, _, e1 := syscall.Syscall(procGetVersion.Addr(), 0, 0, 0, 0)
 	ver = uint32(r0)
 	if ver == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -745,11 +637,7 @@
 	r0, _, e1 := syscall.Syscall9(procFormatMessageW.Addr(), 7, uintptr(flags), uintptr(msgsrc), uintptr(msgid), uintptr(langid), uintptr(unsafe.Pointer(_p0)), uintptr(len(buf)), uintptr(unsafe.Pointer(args)), 0, 0)
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -767,11 +655,7 @@
 	r1, _, e1 := syscall.Syscall(procIsWow64Process.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(&_p0)), 0)
 	*isWow64 = _p0 != 0
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -780,11 +664,7 @@
 	r0, _, e1 := syscall.Syscall9(procCreateFileW.Addr(), 7, uintptr(unsafe.Pointer(name)), uintptr(access), uintptr(mode), uintptr(unsafe.Pointer(sa)), uintptr(createmode), uintptr(attrs), uintptr(templatefile), 0, 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -796,11 +676,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procReadFile.Addr(), 5, uintptr(handle), uintptr(unsafe.Pointer(_p0)), uintptr(len(buf)), uintptr(unsafe.Pointer(done)), uintptr(unsafe.Pointer(overlapped)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -812,11 +688,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procWriteFile.Addr(), 5, uintptr(handle), uintptr(unsafe.Pointer(_p0)), uintptr(len(buf)), uintptr(unsafe.Pointer(done)), uintptr(unsafe.Pointer(overlapped)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -828,11 +700,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procGetOverlappedResult.Addr(), 4, uintptr(handle), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(done)), uintptr(_p0), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -841,11 +709,7 @@
 	r0, _, e1 := syscall.Syscall6(procSetFilePointer.Addr(), 4, uintptr(handle), uintptr(lowoffset), uintptr(unsafe.Pointer(highoffsetptr)), uintptr(whence), 0, 0)
 	newlowoffset = uint32(r0)
 	if newlowoffset == 0xffffffff {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -853,11 +717,7 @@
 func CloseHandle(handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procCloseHandle.Addr(), 1, uintptr(handle), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -866,11 +726,7 @@
 	r0, _, e1 := syscall.Syscall(procGetStdHandle.Addr(), 1, uintptr(stdhandle), 0, 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -878,11 +734,7 @@
 func SetStdHandle(stdhandle uint32, handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetStdHandle.Addr(), 2, uintptr(stdhandle), uintptr(handle), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -891,11 +743,7 @@
 	r0, _, e1 := syscall.Syscall(procFindFirstFileW.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(data)), 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -903,11 +751,7 @@
 func findNextFile1(handle Handle, data *win32finddata1) (err error) {
 	r1, _, e1 := syscall.Syscall(procFindNextFileW.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(data)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -915,11 +759,7 @@
 func FindClose(handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procFindClose.Addr(), 1, uintptr(handle), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -927,11 +767,7 @@
 func GetFileInformationByHandle(handle Handle, data *ByHandleFileInformation) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetFileInformationByHandle.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(data)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -939,11 +775,7 @@
 func GetFileInformationByHandleEx(handle Handle, class uint32, outBuffer *byte, outBufferLen uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetFileInformationByHandleEx.Addr(), 4, uintptr(handle), uintptr(class), uintptr(unsafe.Pointer(outBuffer)), uintptr(outBufferLen), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -952,11 +784,7 @@
 	r0, _, e1 := syscall.Syscall(procGetCurrentDirectoryW.Addr(), 2, uintptr(buflen), uintptr(unsafe.Pointer(buf)), 0)
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -964,11 +792,7 @@
 func SetCurrentDirectory(path *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetCurrentDirectoryW.Addr(), 1, uintptr(unsafe.Pointer(path)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -976,11 +800,7 @@
 func CreateDirectory(path *uint16, sa *SecurityAttributes) (err error) {
 	r1, _, e1 := syscall.Syscall(procCreateDirectoryW.Addr(), 2, uintptr(unsafe.Pointer(path)), uintptr(unsafe.Pointer(sa)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -988,11 +808,7 @@
 func RemoveDirectory(path *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procRemoveDirectoryW.Addr(), 1, uintptr(unsafe.Pointer(path)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1000,11 +816,7 @@
 func DeleteFile(path *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procDeleteFileW.Addr(), 1, uintptr(unsafe.Pointer(path)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1012,11 +824,7 @@
 func MoveFile(from *uint16, to *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procMoveFileW.Addr(), 2, uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(to)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1024,11 +832,7 @@
 func MoveFileEx(from *uint16, to *uint16, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procMoveFileExW.Addr(), 3, uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(to)), uintptr(flags))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1036,11 +840,7 @@
 func LockFileEx(file Handle, flags uint32, reserved uint32, bytesLow uint32, bytesHigh uint32, overlapped *Overlapped) (err error) {
 	r1, _, e1 := syscall.Syscall6(procLockFileEx.Addr(), 6, uintptr(file), uintptr(flags), uintptr(reserved), uintptr(bytesLow), uintptr(bytesHigh), uintptr(unsafe.Pointer(overlapped)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1048,11 +848,7 @@
 func UnlockFileEx(file Handle, reserved uint32, bytesLow uint32, bytesHigh uint32, overlapped *Overlapped) (err error) {
 	r1, _, e1 := syscall.Syscall6(procUnlockFileEx.Addr(), 5, uintptr(file), uintptr(reserved), uintptr(bytesLow), uintptr(bytesHigh), uintptr(unsafe.Pointer(overlapped)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1060,11 +856,7 @@
 func GetComputerName(buf *uint16, n *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetComputerNameW.Addr(), 2, uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(n)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1072,11 +864,7 @@
 func GetComputerNameEx(nametype uint32, buf *uint16, n *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetComputerNameExW.Addr(), 3, uintptr(nametype), uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(n)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1084,11 +872,7 @@
 func SetEndOfFile(handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetEndOfFile.Addr(), 1, uintptr(handle), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1107,11 +891,7 @@
 	r0, _, e1 := syscall.Syscall(procGetTimeZoneInformation.Addr(), 1, uintptr(unsafe.Pointer(tzi)), 0, 0)
 	rc = uint32(r0)
 	if rc == 0xffffffff {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1120,11 +900,7 @@
 	r0, _, e1 := syscall.Syscall6(procCreateIoCompletionPort.Addr(), 4, uintptr(filehandle), uintptr(cphandle), uintptr(key), uintptr(threadcnt), 0, 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1132,11 +908,7 @@
 func GetQueuedCompletionStatus(cphandle Handle, qty *uint32, key *uint32, overlapped **Overlapped, timeout uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetQueuedCompletionStatus.Addr(), 5, uintptr(cphandle), uintptr(unsafe.Pointer(qty)), uintptr(unsafe.Pointer(key)), uintptr(unsafe.Pointer(overlapped)), uintptr(timeout), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1144,11 +916,7 @@
 func PostQueuedCompletionStatus(cphandle Handle, qty uint32, key uint32, overlapped *Overlapped) (err error) {
 	r1, _, e1 := syscall.Syscall6(procPostQueuedCompletionStatus.Addr(), 4, uintptr(cphandle), uintptr(qty), uintptr(key), uintptr(unsafe.Pointer(overlapped)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1156,11 +924,7 @@
 func CancelIo(s Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procCancelIo.Addr(), 1, uintptr(s), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1168,11 +932,7 @@
 func CancelIoEx(s Handle, o *Overlapped) (err error) {
 	r1, _, e1 := syscall.Syscall(procCancelIoEx.Addr(), 2, uintptr(s), uintptr(unsafe.Pointer(o)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1184,11 +944,7 @@
 	}
 	r1, _, e1 := syscall.Syscall12(procCreateProcessW.Addr(), 10, uintptr(unsafe.Pointer(appName)), uintptr(unsafe.Pointer(commandLine)), uintptr(unsafe.Pointer(procSecurity)), uintptr(unsafe.Pointer(threadSecurity)), uintptr(_p0), uintptr(creationFlags), uintptr(unsafe.Pointer(env)), uintptr(unsafe.Pointer(currentDir)), uintptr(unsafe.Pointer(startupInfo)), uintptr(unsafe.Pointer(outProcInfo)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1201,11 +957,7 @@
 	r0, _, e1 := syscall.Syscall(procOpenProcess.Addr(), 3, uintptr(desiredAccess), uintptr(_p0), uintptr(processId))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1213,11 +965,7 @@
 func ShellExecute(hwnd Handle, verb *uint16, file *uint16, args *uint16, cwd *uint16, showCmd int32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procShellExecuteW.Addr(), 6, uintptr(hwnd), uintptr(unsafe.Pointer(verb)), uintptr(unsafe.Pointer(file)), uintptr(unsafe.Pointer(args)), uintptr(unsafe.Pointer(cwd)), uintptr(showCmd))
 	if r1 <= 32 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1233,11 +981,7 @@
 func TerminateProcess(handle Handle, exitcode uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procTerminateProcess.Addr(), 2, uintptr(handle), uintptr(exitcode), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1245,11 +989,7 @@
 func GetExitCodeProcess(handle Handle, exitcode *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetExitCodeProcess.Addr(), 2, uintptr(handle), uintptr(unsafe.Pointer(exitcode)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1257,11 +997,7 @@
 func GetStartupInfo(startupInfo *StartupInfo) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetStartupInfoW.Addr(), 1, uintptr(unsafe.Pointer(startupInfo)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1269,11 +1005,7 @@
 func GetProcessTimes(handle Handle, creationTime *Filetime, exitTime *Filetime, kernelTime *Filetime, userTime *Filetime) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetProcessTimes.Addr(), 5, uintptr(handle), uintptr(unsafe.Pointer(creationTime)), uintptr(unsafe.Pointer(exitTime)), uintptr(unsafe.Pointer(kernelTime)), uintptr(unsafe.Pointer(userTime)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1285,11 +1017,7 @@
 	}
 	r1, _, e1 := syscall.Syscall9(procDuplicateHandle.Addr(), 7, uintptr(hSourceProcessHandle), uintptr(hSourceHandle), uintptr(hTargetProcessHandle), uintptr(unsafe.Pointer(lpTargetHandle)), uintptr(dwDesiredAccess), uintptr(_p0), uintptr(dwOptions), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1298,11 +1026,7 @@
 	r0, _, e1 := syscall.Syscall(procWaitForSingleObject.Addr(), 2, uintptr(handle), uintptr(waitMilliseconds), 0)
 	event = uint32(r0)
 	if event == 0xffffffff {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1315,11 +1039,7 @@
 	r0, _, e1 := syscall.Syscall6(procWaitForMultipleObjects.Addr(), 4, uintptr(count), uintptr(handles), uintptr(_p0), uintptr(waitMilliseconds), 0, 0)
 	event = uint32(r0)
 	if event == 0xffffffff {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1328,11 +1048,7 @@
 	r0, _, e1 := syscall.Syscall(procGetTempPathW.Addr(), 2, uintptr(buflen), uintptr(unsafe.Pointer(buf)), 0)
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1340,11 +1056,7 @@
 func CreatePipe(readhandle *Handle, writehandle *Handle, sa *SecurityAttributes, size uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procCreatePipe.Addr(), 4, uintptr(unsafe.Pointer(readhandle)), uintptr(unsafe.Pointer(writehandle)), uintptr(unsafe.Pointer(sa)), uintptr(size), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1353,11 +1065,7 @@
 	r0, _, e1 := syscall.Syscall(procGetFileType.Addr(), 1, uintptr(filehandle), 0, 0)
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1365,11 +1073,7 @@
 func CryptAcquireContext(provhandle *Handle, container *uint16, provider *uint16, provtype uint32, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procCryptAcquireContextW.Addr(), 5, uintptr(unsafe.Pointer(provhandle)), uintptr(unsafe.Pointer(container)), uintptr(unsafe.Pointer(provider)), uintptr(provtype), uintptr(flags), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1377,11 +1081,7 @@
 func CryptReleaseContext(provhandle Handle, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procCryptReleaseContext.Addr(), 2, uintptr(provhandle), uintptr(flags), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1389,11 +1089,7 @@
 func CryptGenRandom(provhandle Handle, buflen uint32, buf *byte) (err error) {
 	r1, _, e1 := syscall.Syscall(procCryptGenRandom.Addr(), 3, uintptr(provhandle), uintptr(buflen), uintptr(unsafe.Pointer(buf)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1402,11 +1098,7 @@
 	r0, _, e1 := syscall.Syscall(procGetEnvironmentStringsW.Addr(), 0, 0, 0, 0)
 	envs = (*uint16)(unsafe.Pointer(r0))
 	if envs == nil {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1414,11 +1106,7 @@
 func FreeEnvironmentStrings(envs *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procFreeEnvironmentStringsW.Addr(), 1, uintptr(unsafe.Pointer(envs)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1427,11 +1115,7 @@
 	r0, _, e1 := syscall.Syscall(procGetEnvironmentVariableW.Addr(), 3, uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(buffer)), uintptr(size))
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1439,11 +1123,7 @@
 func SetEnvironmentVariable(name *uint16, value *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetEnvironmentVariableW.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(value)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1455,11 +1135,7 @@
 	}
 	r1, _, e1 := syscall.Syscall(procCreateEnvironmentBlock.Addr(), 3, uintptr(unsafe.Pointer(block)), uintptr(token), uintptr(_p0))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1467,11 +1143,7 @@
 func DestroyEnvironmentBlock(block *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procDestroyEnvironmentBlock.Addr(), 1, uintptr(unsafe.Pointer(block)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1485,11 +1157,7 @@
 func SetFileTime(handle Handle, ctime *Filetime, atime *Filetime, wtime *Filetime) (err error) {
 	r1, _, e1 := syscall.Syscall6(procSetFileTime.Addr(), 4, uintptr(handle), uintptr(unsafe.Pointer(ctime)), uintptr(unsafe.Pointer(atime)), uintptr(unsafe.Pointer(wtime)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1498,11 +1166,7 @@
 	r0, _, e1 := syscall.Syscall(procGetFileAttributesW.Addr(), 1, uintptr(unsafe.Pointer(name)), 0, 0)
 	attrs = uint32(r0)
 	if attrs == INVALID_FILE_ATTRIBUTES {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1510,11 +1174,7 @@
 func SetFileAttributes(name *uint16, attrs uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetFileAttributesW.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(attrs), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1522,11 +1182,7 @@
 func GetFileAttributesEx(name *uint16, level uint32, info *byte) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetFileAttributesExW.Addr(), 3, uintptr(unsafe.Pointer(name)), uintptr(level), uintptr(unsafe.Pointer(info)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1541,11 +1197,7 @@
 	r0, _, e1 := syscall.Syscall(procCommandLineToArgvW.Addr(), 2, uintptr(unsafe.Pointer(cmd)), uintptr(unsafe.Pointer(argc)), 0)
 	argv = (*[8192]*[8192]uint16)(unsafe.Pointer(r0))
 	if argv == nil {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1554,11 +1206,7 @@
 	r0, _, e1 := syscall.Syscall(procLocalFree.Addr(), 1, uintptr(hmem), 0, 0)
 	handle = Handle(r0)
 	if handle != 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1566,11 +1214,7 @@
 func SetHandleInformation(handle Handle, mask uint32, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetHandleInformation.Addr(), 3, uintptr(handle), uintptr(mask), uintptr(flags))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1578,11 +1222,7 @@
 func FlushFileBuffers(handle Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procFlushFileBuffers.Addr(), 1, uintptr(handle), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1591,11 +1231,7 @@
 	r0, _, e1 := syscall.Syscall6(procGetFullPathNameW.Addr(), 4, uintptr(unsafe.Pointer(path)), uintptr(buflen), uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(fname)), 0, 0)
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1604,11 +1240,7 @@
 	r0, _, e1 := syscall.Syscall(procGetLongPathNameW.Addr(), 3, uintptr(unsafe.Pointer(path)), uintptr(unsafe.Pointer(buf)), uintptr(buflen))
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1617,11 +1249,7 @@
 	r0, _, e1 := syscall.Syscall(procGetShortPathNameW.Addr(), 3, uintptr(unsafe.Pointer(longpath)), uintptr(unsafe.Pointer(shortpath)), uintptr(buflen))
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1630,11 +1258,7 @@
 	r0, _, e1 := syscall.Syscall6(procCreateFileMappingW.Addr(), 6, uintptr(fhandle), uintptr(unsafe.Pointer(sa)), uintptr(prot), uintptr(maxSizeHigh), uintptr(maxSizeLow), uintptr(unsafe.Pointer(name)))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1643,11 +1267,7 @@
 	r0, _, e1 := syscall.Syscall6(procMapViewOfFile.Addr(), 5, uintptr(handle), uintptr(access), uintptr(offsetHigh), uintptr(offsetLow), uintptr(length), 0)
 	addr = uintptr(r0)
 	if addr == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1655,11 +1275,7 @@
 func UnmapViewOfFile(addr uintptr) (err error) {
 	r1, _, e1 := syscall.Syscall(procUnmapViewOfFile.Addr(), 1, uintptr(addr), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1667,11 +1283,7 @@
 func FlushViewOfFile(addr uintptr, length uintptr) (err error) {
 	r1, _, e1 := syscall.Syscall(procFlushViewOfFile.Addr(), 2, uintptr(addr), uintptr(length), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1679,11 +1291,7 @@
 func VirtualLock(addr uintptr, length uintptr) (err error) {
 	r1, _, e1 := syscall.Syscall(procVirtualLock.Addr(), 2, uintptr(addr), uintptr(length), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1691,11 +1299,7 @@
 func VirtualUnlock(addr uintptr, length uintptr) (err error) {
 	r1, _, e1 := syscall.Syscall(procVirtualUnlock.Addr(), 2, uintptr(addr), uintptr(length), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1704,11 +1308,7 @@
 	r0, _, e1 := syscall.Syscall6(procVirtualAlloc.Addr(), 4, uintptr(address), uintptr(size), uintptr(alloctype), uintptr(protect), 0, 0)
 	value = uintptr(r0)
 	if value == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1716,11 +1316,7 @@
 func VirtualFree(address uintptr, size uintptr, freetype uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procVirtualFree.Addr(), 3, uintptr(address), uintptr(size), uintptr(freetype))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1728,11 +1324,7 @@
 func VirtualProtect(address uintptr, size uintptr, newprotect uint32, oldprotect *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procVirtualProtect.Addr(), 4, uintptr(address), uintptr(size), uintptr(newprotect), uintptr(unsafe.Pointer(oldprotect)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1740,11 +1332,7 @@
 func TransmitFile(s Handle, handle Handle, bytesToWrite uint32, bytsPerSend uint32, overlapped *Overlapped, transmitFileBuf *TransmitFileBuffers, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall9(procTransmitFile.Addr(), 7, uintptr(s), uintptr(handle), uintptr(bytesToWrite), uintptr(bytsPerSend), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(transmitFileBuf)), uintptr(flags), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1756,11 +1344,7 @@
 	}
 	r1, _, e1 := syscall.Syscall9(procReadDirectoryChangesW.Addr(), 8, uintptr(handle), uintptr(unsafe.Pointer(buf)), uintptr(buflen), uintptr(_p0), uintptr(mask), uintptr(unsafe.Pointer(retlen)), uintptr(unsafe.Pointer(overlapped)), uintptr(completionRoutine), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1769,11 +1353,7 @@
 	r0, _, e1 := syscall.Syscall(procCertOpenSystemStoreW.Addr(), 2, uintptr(hprov), uintptr(unsafe.Pointer(name)), 0)
 	store = Handle(r0)
 	if store == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1782,11 +1362,7 @@
 	r0, _, e1 := syscall.Syscall6(procCertOpenStore.Addr(), 5, uintptr(storeProvider), uintptr(msgAndCertEncodingType), uintptr(cryptProv), uintptr(flags), uintptr(para), 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1795,11 +1371,7 @@
 	r0, _, e1 := syscall.Syscall(procCertEnumCertificatesInStore.Addr(), 2, uintptr(store), uintptr(unsafe.Pointer(prevContext)), 0)
 	context = (*CertContext)(unsafe.Pointer(r0))
 	if context == nil {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1807,11 +1379,7 @@
 func CertAddCertificateContextToStore(store Handle, certContext *CertContext, addDisposition uint32, storeContext **CertContext) (err error) {
 	r1, _, e1 := syscall.Syscall6(procCertAddCertificateContextToStore.Addr(), 4, uintptr(store), uintptr(unsafe.Pointer(certContext)), uintptr(addDisposition), uintptr(unsafe.Pointer(storeContext)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1819,11 +1387,7 @@
 func CertCloseStore(store Handle, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procCertCloseStore.Addr(), 2, uintptr(store), uintptr(flags), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1831,11 +1395,7 @@
 func CertGetCertificateChain(engine Handle, leaf *CertContext, time *Filetime, additionalStore Handle, para *CertChainPara, flags uint32, reserved uintptr, chainCtx **CertChainContext) (err error) {
 	r1, _, e1 := syscall.Syscall9(procCertGetCertificateChain.Addr(), 8, uintptr(engine), uintptr(unsafe.Pointer(leaf)), uintptr(unsafe.Pointer(time)), uintptr(additionalStore), uintptr(unsafe.Pointer(para)), uintptr(flags), uintptr(reserved), uintptr(unsafe.Pointer(chainCtx)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1849,11 +1409,7 @@
 	r0, _, e1 := syscall.Syscall(procCertCreateCertificateContext.Addr(), 3, uintptr(certEncodingType), uintptr(unsafe.Pointer(certEncoded)), uintptr(encodedLen))
 	context = (*CertContext)(unsafe.Pointer(r0))
 	if context == nil {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1861,11 +1417,7 @@
 func CertFreeCertificateContext(ctx *CertContext) (err error) {
 	r1, _, e1 := syscall.Syscall(procCertFreeCertificateContext.Addr(), 1, uintptr(unsafe.Pointer(ctx)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1873,11 +1425,7 @@
 func CertVerifyCertificateChainPolicy(policyOID uintptr, chain *CertChainContext, para *CertChainPolicyPara, status *CertChainPolicyStatus) (err error) {
 	r1, _, e1 := syscall.Syscall6(procCertVerifyCertificateChainPolicy.Addr(), 4, uintptr(policyOID), uintptr(unsafe.Pointer(chain)), uintptr(unsafe.Pointer(para)), uintptr(unsafe.Pointer(status)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1931,11 +1479,7 @@
 func ProcessIdToSessionId(pid uint32, sessionid *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procProcessIdToSessionId.Addr(), 2, uintptr(pid), uintptr(unsafe.Pointer(sessionid)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1943,11 +1487,7 @@
 func GetConsoleMode(console Handle, mode *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetConsoleMode.Addr(), 2, uintptr(console), uintptr(unsafe.Pointer(mode)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1955,11 +1495,7 @@
 func SetConsoleMode(console Handle, mode uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetConsoleMode.Addr(), 2, uintptr(console), uintptr(mode), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1967,11 +1503,7 @@
 func GetConsoleScreenBufferInfo(console Handle, info *ConsoleScreenBufferInfo) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetConsoleScreenBufferInfo.Addr(), 2, uintptr(console), uintptr(unsafe.Pointer(info)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1979,11 +1511,7 @@
 func SetConsoleCursorPosition(console Handle, position Coord) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetConsoleCursorPosition.Addr(), 2, uintptr(console), uintptr(*((*uint32)(unsafe.Pointer(&position)))), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -1991,11 +1519,7 @@
 func WriteConsole(console Handle, buf *uint16, towrite uint32, written *uint32, reserved *byte) (err error) {
 	r1, _, e1 := syscall.Syscall6(procWriteConsoleW.Addr(), 5, uintptr(console), uintptr(unsafe.Pointer(buf)), uintptr(towrite), uintptr(unsafe.Pointer(written)), uintptr(unsafe.Pointer(reserved)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2003,11 +1527,7 @@
 func ReadConsole(console Handle, buf *uint16, toread uint32, read *uint32, inputControl *byte) (err error) {
 	r1, _, e1 := syscall.Syscall6(procReadConsoleW.Addr(), 5, uintptr(console), uintptr(unsafe.Pointer(buf)), uintptr(toread), uintptr(unsafe.Pointer(read)), uintptr(unsafe.Pointer(inputControl)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2016,11 +1536,7 @@
 	r0, _, e1 := syscall.Syscall(procCreateToolhelp32Snapshot.Addr(), 2, uintptr(flags), uintptr(processId), 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2028,11 +1544,7 @@
 func Process32First(snapshot Handle, procEntry *ProcessEntry32) (err error) {
 	r1, _, e1 := syscall.Syscall(procProcess32FirstW.Addr(), 2, uintptr(snapshot), uintptr(unsafe.Pointer(procEntry)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2040,11 +1552,7 @@
 func Process32Next(snapshot Handle, procEntry *ProcessEntry32) (err error) {
 	r1, _, e1 := syscall.Syscall(procProcess32NextW.Addr(), 2, uintptr(snapshot), uintptr(unsafe.Pointer(procEntry)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2052,11 +1560,7 @@
 func Thread32First(snapshot Handle, threadEntry *ThreadEntry32) (err error) {
 	r1, _, e1 := syscall.Syscall(procThread32First.Addr(), 2, uintptr(snapshot), uintptr(unsafe.Pointer(threadEntry)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2064,11 +1568,7 @@
 func Thread32Next(snapshot Handle, threadEntry *ThreadEntry32) (err error) {
 	r1, _, e1 := syscall.Syscall(procThread32Next.Addr(), 2, uintptr(snapshot), uintptr(unsafe.Pointer(threadEntry)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2076,11 +1576,7 @@
 func DeviceIoControl(handle Handle, ioControlCode uint32, inBuffer *byte, inBufferSize uint32, outBuffer *byte, outBufferSize uint32, bytesReturned *uint32, overlapped *Overlapped) (err error) {
 	r1, _, e1 := syscall.Syscall9(procDeviceIoControl.Addr(), 8, uintptr(handle), uintptr(ioControlCode), uintptr(unsafe.Pointer(inBuffer)), uintptr(inBufferSize), uintptr(unsafe.Pointer(outBuffer)), uintptr(outBufferSize), uintptr(unsafe.Pointer(bytesReturned)), uintptr(unsafe.Pointer(overlapped)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2088,11 +1584,7 @@
 func CreateSymbolicLink(symlinkfilename *uint16, targetfilename *uint16, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procCreateSymbolicLinkW.Addr(), 3, uintptr(unsafe.Pointer(symlinkfilename)), uintptr(unsafe.Pointer(targetfilename)), uintptr(flags))
 	if r1&0xff == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2100,11 +1592,7 @@
 func CreateHardLink(filename *uint16, existingfilename *uint16, reserved uintptr) (err error) {
 	r1, _, e1 := syscall.Syscall(procCreateHardLinkW.Addr(), 3, uintptr(unsafe.Pointer(filename)), uintptr(unsafe.Pointer(existingfilename)), uintptr(reserved))
 	if r1&0xff == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2119,11 +1607,7 @@
 	r0, _, e1 := syscall.Syscall6(procCreateEventW.Addr(), 4, uintptr(unsafe.Pointer(eventAttrs)), uintptr(manualReset), uintptr(initialState), uintptr(unsafe.Pointer(name)), 0, 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2132,11 +1616,7 @@
 	r0, _, e1 := syscall.Syscall6(procCreateEventExW.Addr(), 4, uintptr(unsafe.Pointer(eventAttrs)), uintptr(unsafe.Pointer(name)), uintptr(flags), uintptr(desiredAccess), 0, 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2149,11 +1629,7 @@
 	r0, _, e1 := syscall.Syscall(procOpenEventW.Addr(), 3, uintptr(desiredAccess), uintptr(_p0), uintptr(unsafe.Pointer(name)))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2161,11 +1637,7 @@
 func SetEvent(event Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetEvent.Addr(), 1, uintptr(event), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2173,11 +1645,7 @@
 func ResetEvent(event Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procResetEvent.Addr(), 1, uintptr(event), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2185,11 +1653,7 @@
 func PulseEvent(event Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procPulseEvent.Addr(), 1, uintptr(event), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2202,11 +1666,7 @@
 	r0, _, e1 := syscall.Syscall(procCreateMutexW.Addr(), 3, uintptr(unsafe.Pointer(mutexAttrs)), uintptr(_p0), uintptr(unsafe.Pointer(name)))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2215,11 +1675,7 @@
 	r0, _, e1 := syscall.Syscall6(procCreateMutexExW.Addr(), 4, uintptr(unsafe.Pointer(mutexAttrs)), uintptr(unsafe.Pointer(name)), uintptr(flags), uintptr(desiredAccess), 0, 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2232,11 +1688,7 @@
 	r0, _, e1 := syscall.Syscall(procOpenMutexW.Addr(), 3, uintptr(desiredAccess), uintptr(_p0), uintptr(unsafe.Pointer(name)))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2244,11 +1696,7 @@
 func ReleaseMutex(mutex Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procReleaseMutex.Addr(), 1, uintptr(mutex), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2267,11 +1715,7 @@
 	r0, _, e1 := syscall.Syscall(procCreateJobObjectW.Addr(), 2, uintptr(unsafe.Pointer(jobAttr)), uintptr(unsafe.Pointer(name)), 0)
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2279,11 +1723,7 @@
 func AssignProcessToJobObject(job Handle, process Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procAssignProcessToJobObject.Addr(), 2, uintptr(job), uintptr(process), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2291,11 +1731,7 @@
 func TerminateJobObject(job Handle, exitCode uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procTerminateJobObject.Addr(), 2, uintptr(job), uintptr(exitCode), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2310,11 +1746,7 @@
 	r0, _, e1 := syscall.Syscall(procResumeThread.Addr(), 1, uintptr(thread), 0, 0)
 	ret = uint32(r0)
 	if ret == 0xffffffff {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2322,11 +1754,7 @@
 func SetPriorityClass(process Handle, priorityClass uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetPriorityClass.Addr(), 2, uintptr(process), uintptr(priorityClass), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2335,11 +1763,7 @@
 	r0, _, e1 := syscall.Syscall(procGetPriorityClass.Addr(), 1, uintptr(process), 0, 0)
 	ret = uint32(r0)
 	if ret == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2347,11 +1771,7 @@
 func QueryInformationJobObject(job Handle, JobObjectInformationClass int32, JobObjectInformation uintptr, JobObjectInformationLength uint32, retlen *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procQueryInformationJobObject.Addr(), 5, uintptr(job), uintptr(JobObjectInformationClass), uintptr(JobObjectInformation), uintptr(JobObjectInformationLength), uintptr(unsafe.Pointer(retlen)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2360,11 +1780,7 @@
 	r0, _, e1 := syscall.Syscall6(procSetInformationJobObject.Addr(), 4, uintptr(job), uintptr(JobObjectInformationClass), uintptr(JobObjectInformation), uintptr(JobObjectInformationLength), 0, 0)
 	ret = int(r0)
 	if ret == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2372,11 +1788,7 @@
 func GenerateConsoleCtrlEvent(ctrlEvent uint32, processGroupID uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGenerateConsoleCtrlEvent.Addr(), 2, uintptr(ctrlEvent), uintptr(processGroupID), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2385,11 +1797,7 @@
 	r0, _, e1 := syscall.Syscall(procGetProcessId.Addr(), 1, uintptr(process), 0, 0)
 	id = uint32(r0)
 	if id == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2402,11 +1810,7 @@
 	r0, _, e1 := syscall.Syscall(procOpenThread.Addr(), 3, uintptr(desiredAccess), uintptr(_p0), uintptr(threadId))
 	handle = Handle(r0)
 	if handle == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2418,11 +1822,7 @@
 	}
 	r1, _, e1 := syscall.Syscall(procSetProcessPriorityBoost.Addr(), 2, uintptr(process), uintptr(_p0), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2435,11 +1835,7 @@
 func SetProcessWorkingSetSizeEx(hProcess Handle, dwMinimumWorkingSetSize uintptr, dwMaximumWorkingSetSize uintptr, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procSetProcessWorkingSetSizeEx.Addr(), 4, uintptr(hProcess), uintptr(dwMinimumWorkingSetSize), uintptr(dwMaximumWorkingSetSize), uintptr(flags), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2447,11 +1843,7 @@
 func DefineDosDevice(flags uint32, deviceName *uint16, targetPath *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procDefineDosDeviceW.Addr(), 3, uintptr(flags), uintptr(unsafe.Pointer(deviceName)), uintptr(unsafe.Pointer(targetPath)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2459,11 +1851,7 @@
 func DeleteVolumeMountPoint(volumeMountPoint *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procDeleteVolumeMountPointW.Addr(), 1, uintptr(unsafe.Pointer(volumeMountPoint)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2472,11 +1860,7 @@
 	r0, _, e1 := syscall.Syscall(procFindFirstVolumeW.Addr(), 2, uintptr(unsafe.Pointer(volumeName)), uintptr(bufferLength), 0)
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2485,11 +1869,7 @@
 	r0, _, e1 := syscall.Syscall(procFindFirstVolumeMountPointW.Addr(), 3, uintptr(unsafe.Pointer(rootPathName)), uintptr(unsafe.Pointer(volumeMountPoint)), uintptr(bufferLength))
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2497,11 +1877,7 @@
 func FindNextVolume(findVolume Handle, volumeName *uint16, bufferLength uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procFindNextVolumeW.Addr(), 3, uintptr(findVolume), uintptr(unsafe.Pointer(volumeName)), uintptr(bufferLength))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2509,11 +1885,7 @@
 func FindNextVolumeMountPoint(findVolumeMountPoint Handle, volumeMountPoint *uint16, bufferLength uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procFindNextVolumeMountPointW.Addr(), 3, uintptr(findVolumeMountPoint), uintptr(unsafe.Pointer(volumeMountPoint)), uintptr(bufferLength))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2521,11 +1893,7 @@
 func FindVolumeClose(findVolume Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procFindVolumeClose.Addr(), 1, uintptr(findVolume), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2533,11 +1901,7 @@
 func FindVolumeMountPointClose(findVolumeMountPoint Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procFindVolumeMountPointClose.Addr(), 1, uintptr(findVolumeMountPoint), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2545,11 +1909,7 @@
 func GetDiskFreeSpaceEx(directoryName *uint16, freeBytesAvailableToCaller *uint64, totalNumberOfBytes *uint64, totalNumberOfFreeBytes *uint64) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetDiskFreeSpaceExW.Addr(), 4, uintptr(unsafe.Pointer(directoryName)), uintptr(unsafe.Pointer(freeBytesAvailableToCaller)), uintptr(unsafe.Pointer(totalNumberOfBytes)), uintptr(unsafe.Pointer(totalNumberOfFreeBytes)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2564,11 +1924,7 @@
 	r0, _, e1 := syscall.Syscall(procGetLogicalDrives.Addr(), 0, 0, 0, 0)
 	drivesBitMask = uint32(r0)
 	if drivesBitMask == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2577,11 +1933,7 @@
 	r0, _, e1 := syscall.Syscall(procGetLogicalDriveStringsW.Addr(), 2, uintptr(bufferLength), uintptr(unsafe.Pointer(buffer)), 0)
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2589,11 +1941,7 @@
 func GetVolumeInformation(rootPathName *uint16, volumeNameBuffer *uint16, volumeNameSize uint32, volumeNameSerialNumber *uint32, maximumComponentLength *uint32, fileSystemFlags *uint32, fileSystemNameBuffer *uint16, fileSystemNameSize uint32) (err error) {
 	r1, _, e1 := syscall.Syscall9(procGetVolumeInformationW.Addr(), 8, uintptr(unsafe.Pointer(rootPathName)), uintptr(unsafe.Pointer(volumeNameBuffer)), uintptr(volumeNameSize), uintptr(unsafe.Pointer(volumeNameSerialNumber)), uintptr(unsafe.Pointer(maximumComponentLength)), uintptr(unsafe.Pointer(fileSystemFlags)), uintptr(unsafe.Pointer(fileSystemNameBuffer)), uintptr(fileSystemNameSize), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2601,11 +1949,7 @@
 func GetVolumeInformationByHandle(file Handle, volumeNameBuffer *uint16, volumeNameSize uint32, volumeNameSerialNumber *uint32, maximumComponentLength *uint32, fileSystemFlags *uint32, fileSystemNameBuffer *uint16, fileSystemNameSize uint32) (err error) {
 	r1, _, e1 := syscall.Syscall9(procGetVolumeInformationByHandleW.Addr(), 8, uintptr(file), uintptr(unsafe.Pointer(volumeNameBuffer)), uintptr(volumeNameSize), uintptr(unsafe.Pointer(volumeNameSerialNumber)), uintptr(unsafe.Pointer(maximumComponentLength)), uintptr(unsafe.Pointer(fileSystemFlags)), uintptr(unsafe.Pointer(fileSystemNameBuffer)), uintptr(fileSystemNameSize), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2613,11 +1957,7 @@
 func GetVolumeNameForVolumeMountPoint(volumeMountPoint *uint16, volumeName *uint16, bufferlength uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetVolumeNameForVolumeMountPointW.Addr(), 3, uintptr(unsafe.Pointer(volumeMountPoint)), uintptr(unsafe.Pointer(volumeName)), uintptr(bufferlength))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2625,11 +1965,7 @@
 func GetVolumePathName(fileName *uint16, volumePathName *uint16, bufferLength uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetVolumePathNameW.Addr(), 3, uintptr(unsafe.Pointer(fileName)), uintptr(unsafe.Pointer(volumePathName)), uintptr(bufferLength))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2637,11 +1973,7 @@
 func GetVolumePathNamesForVolumeName(volumeName *uint16, volumePathNames *uint16, bufferLength uint32, returnLength *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetVolumePathNamesForVolumeNameW.Addr(), 4, uintptr(unsafe.Pointer(volumeName)), uintptr(unsafe.Pointer(volumePathNames)), uintptr(bufferLength), uintptr(unsafe.Pointer(returnLength)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2650,11 +1982,7 @@
 	r0, _, e1 := syscall.Syscall(procQueryDosDeviceW.Addr(), 3, uintptr(unsafe.Pointer(deviceName)), uintptr(unsafe.Pointer(targetPath)), uintptr(max))
 	n = uint32(r0)
 	if n == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2662,11 +1990,7 @@
 func SetVolumeLabel(rootPathName *uint16, volumeName *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetVolumeLabelW.Addr(), 2, uintptr(unsafe.Pointer(rootPathName)), uintptr(unsafe.Pointer(volumeName)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2674,11 +1998,7 @@
 func SetVolumeMountPoint(volumeMountPoint *uint16, volumeName *uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetVolumeMountPointW.Addr(), 2, uintptr(unsafe.Pointer(volumeMountPoint)), uintptr(unsafe.Pointer(volumeName)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2687,11 +2007,7 @@
 	r0, _, e1 := syscall.Syscall6(procMessageBoxW.Addr(), 4, uintptr(hwnd), uintptr(unsafe.Pointer(text)), uintptr(unsafe.Pointer(caption)), uintptr(boxtype), 0, 0)
 	ret = int32(r0)
 	if ret == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2699,11 +2015,7 @@
 func ExitWindowsEx(flags uint32, reason uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procExitWindowsEx.Addr(), 2, uintptr(flags), uintptr(reason), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2719,11 +2031,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procInitiateSystemShutdownExW.Addr(), 6, uintptr(unsafe.Pointer(machineName)), uintptr(unsafe.Pointer(message)), uintptr(timeout), uintptr(_p0), uintptr(_p1), uintptr(reason))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2731,11 +2039,7 @@
 func SetProcessShutdownParameters(level uint32, flags uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetProcessShutdownParameters.Addr(), 2, uintptr(level), uintptr(flags), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2743,11 +2047,7 @@
 func GetProcessShutdownParameters(level *uint32, flags *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetProcessShutdownParameters.Addr(), 2, uintptr(unsafe.Pointer(level)), uintptr(unsafe.Pointer(flags)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2795,11 +2095,7 @@
 func getProcessPreferredUILanguages(flags uint32, numLanguages *uint32, buf *uint16, bufSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetProcessPreferredUILanguages.Addr(), 4, uintptr(flags), uintptr(unsafe.Pointer(numLanguages)), uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(bufSize)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2807,11 +2103,7 @@
 func getThreadPreferredUILanguages(flags uint32, numLanguages *uint32, buf *uint16, bufSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetThreadPreferredUILanguages.Addr(), 4, uintptr(flags), uintptr(unsafe.Pointer(numLanguages)), uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(bufSize)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2819,11 +2111,7 @@
 func getUserPreferredUILanguages(flags uint32, numLanguages *uint32, buf *uint16, bufSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetUserPreferredUILanguages.Addr(), 4, uintptr(flags), uintptr(unsafe.Pointer(numLanguages)), uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(bufSize)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2831,11 +2119,7 @@
 func getSystemPreferredUILanguages(flags uint32, numLanguages *uint32, buf *uint16, bufSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetSystemPreferredUILanguages.Addr(), 4, uintptr(flags), uintptr(unsafe.Pointer(numLanguages)), uintptr(unsafe.Pointer(buf)), uintptr(unsafe.Pointer(bufSize)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2847,11 +2131,7 @@
 	}
 	r1, _, e1 := syscall.Syscall(procEnumProcesses.Addr(), 3, uintptr(unsafe.Pointer(_p0)), uintptr(len(processIds)), uintptr(unsafe.Pointer(bytesReturned)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2867,11 +2147,7 @@
 func WSACleanup() (err error) {
 	r1, _, e1 := syscall.Syscall(procWSACleanup.Addr(), 0, 0, 0, 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2879,11 +2155,7 @@
 func WSAIoctl(s Handle, iocc uint32, inbuf *byte, cbif uint32, outbuf *byte, cbob uint32, cbbr *uint32, overlapped *Overlapped, completionRoutine uintptr) (err error) {
 	r1, _, e1 := syscall.Syscall9(procWSAIoctl.Addr(), 9, uintptr(s), uintptr(iocc), uintptr(unsafe.Pointer(inbuf)), uintptr(cbif), uintptr(unsafe.Pointer(outbuf)), uintptr(cbob), uintptr(unsafe.Pointer(cbbr)), uintptr(unsafe.Pointer(overlapped)), uintptr(completionRoutine))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2892,11 +2164,7 @@
 	r0, _, e1 := syscall.Syscall(procsocket.Addr(), 3, uintptr(af), uintptr(typ), uintptr(protocol))
 	handle = Handle(r0)
 	if handle == InvalidHandle {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2908,11 +2176,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procsendto.Addr(), 6, uintptr(s), uintptr(unsafe.Pointer(_p0)), uintptr(len(buf)), uintptr(flags), uintptr(to), uintptr(tolen))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2925,11 +2189,7 @@
 	r0, _, e1 := syscall.Syscall6(procrecvfrom.Addr(), 6, uintptr(s), uintptr(unsafe.Pointer(_p0)), uintptr(len(buf)), uintptr(flags), uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(fromlen)))
 	n = int32(r0)
 	if n == -1 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2937,11 +2197,7 @@
 func Setsockopt(s Handle, level int32, optname int32, optval *byte, optlen int32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procsetsockopt.Addr(), 5, uintptr(s), uintptr(level), uintptr(optname), uintptr(unsafe.Pointer(optval)), uintptr(optlen), 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2949,11 +2205,7 @@
 func Getsockopt(s Handle, level int32, optname int32, optval *byte, optlen *int32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procgetsockopt.Addr(), 5, uintptr(s), uintptr(level), uintptr(optname), uintptr(unsafe.Pointer(optval)), uintptr(unsafe.Pointer(optlen)), 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2961,11 +2213,7 @@
 func bind(s Handle, name unsafe.Pointer, namelen int32) (err error) {
 	r1, _, e1 := syscall.Syscall(procbind.Addr(), 3, uintptr(s), uintptr(name), uintptr(namelen))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2973,11 +2221,7 @@
 func connect(s Handle, name unsafe.Pointer, namelen int32) (err error) {
 	r1, _, e1 := syscall.Syscall(procconnect.Addr(), 3, uintptr(s), uintptr(name), uintptr(namelen))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2985,11 +2229,7 @@
 func getsockname(s Handle, rsa *RawSockaddrAny, addrlen *int32) (err error) {
 	r1, _, e1 := syscall.Syscall(procgetsockname.Addr(), 3, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -2997,11 +2237,7 @@
 func getpeername(s Handle, rsa *RawSockaddrAny, addrlen *int32) (err error) {
 	r1, _, e1 := syscall.Syscall(procgetpeername.Addr(), 3, uintptr(s), uintptr(unsafe.Pointer(rsa)), uintptr(unsafe.Pointer(addrlen)))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3009,11 +2245,7 @@
 func listen(s Handle, backlog int32) (err error) {
 	r1, _, e1 := syscall.Syscall(proclisten.Addr(), 2, uintptr(s), uintptr(backlog), 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3021,11 +2253,7 @@
 func shutdown(s Handle, how int32) (err error) {
 	r1, _, e1 := syscall.Syscall(procshutdown.Addr(), 2, uintptr(s), uintptr(how), 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3033,11 +2261,7 @@
 func Closesocket(s Handle) (err error) {
 	r1, _, e1 := syscall.Syscall(procclosesocket.Addr(), 1, uintptr(s), 0, 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3045,11 +2269,7 @@
 func AcceptEx(ls Handle, as Handle, buf *byte, rxdatalen uint32, laddrlen uint32, raddrlen uint32, recvd *uint32, overlapped *Overlapped) (err error) {
 	r1, _, e1 := syscall.Syscall9(procAcceptEx.Addr(), 8, uintptr(ls), uintptr(as), uintptr(unsafe.Pointer(buf)), uintptr(rxdatalen), uintptr(laddrlen), uintptr(raddrlen), uintptr(unsafe.Pointer(recvd)), uintptr(unsafe.Pointer(overlapped)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3062,11 +2282,7 @@
 func WSARecv(s Handle, bufs *WSABuf, bufcnt uint32, recvd *uint32, flags *uint32, overlapped *Overlapped, croutine *byte) (err error) {
 	r1, _, e1 := syscall.Syscall9(procWSARecv.Addr(), 7, uintptr(s), uintptr(unsafe.Pointer(bufs)), uintptr(bufcnt), uintptr(unsafe.Pointer(recvd)), uintptr(unsafe.Pointer(flags)), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(croutine)), 0, 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3074,11 +2290,7 @@
 func WSASend(s Handle, bufs *WSABuf, bufcnt uint32, sent *uint32, flags uint32, overlapped *Overlapped, croutine *byte) (err error) {
 	r1, _, e1 := syscall.Syscall9(procWSASend.Addr(), 7, uintptr(s), uintptr(unsafe.Pointer(bufs)), uintptr(bufcnt), uintptr(unsafe.Pointer(sent)), uintptr(flags), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(croutine)), 0, 0)
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3086,11 +2298,7 @@
 func WSARecvFrom(s Handle, bufs *WSABuf, bufcnt uint32, recvd *uint32, flags *uint32, from *RawSockaddrAny, fromlen *int32, overlapped *Overlapped, croutine *byte) (err error) {
 	r1, _, e1 := syscall.Syscall9(procWSARecvFrom.Addr(), 9, uintptr(s), uintptr(unsafe.Pointer(bufs)), uintptr(bufcnt), uintptr(unsafe.Pointer(recvd)), uintptr(unsafe.Pointer(flags)), uintptr(unsafe.Pointer(from)), uintptr(unsafe.Pointer(fromlen)), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(croutine)))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3098,11 +2306,7 @@
 func WSASendTo(s Handle, bufs *WSABuf, bufcnt uint32, sent *uint32, flags uint32, to *RawSockaddrAny, tolen int32, overlapped *Overlapped, croutine *byte) (err error) {
 	r1, _, e1 := syscall.Syscall9(procWSASendTo.Addr(), 9, uintptr(s), uintptr(unsafe.Pointer(bufs)), uintptr(bufcnt), uintptr(unsafe.Pointer(sent)), uintptr(flags), uintptr(unsafe.Pointer(to)), uintptr(tolen), uintptr(unsafe.Pointer(overlapped)), uintptr(unsafe.Pointer(croutine)))
 	if r1 == socket_error {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3120,11 +2324,7 @@
 	r0, _, e1 := syscall.Syscall(procgethostbyname.Addr(), 1, uintptr(unsafe.Pointer(name)), 0, 0)
 	h = (*Hostent)(unsafe.Pointer(r0))
 	if h == nil {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3147,11 +2347,7 @@
 	r0, _, e1 := syscall.Syscall(procgetservbyname.Addr(), 2, uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(proto)), 0)
 	s = (*Servent)(unsafe.Pointer(r0))
 	if s == nil {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3175,11 +2371,7 @@
 	r0, _, e1 := syscall.Syscall(procgetprotobyname.Addr(), 1, uintptr(unsafe.Pointer(name)), 0, 0)
 	p = (*Protoent)(unsafe.Pointer(r0))
 	if p == nil {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3244,11 +2436,7 @@
 func SetFileCompletionNotificationModes(handle Handle, flags uint8) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetFileCompletionNotificationModes.Addr(), 2, uintptr(handle), uintptr(flags), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3257,11 +2445,7 @@
 	r0, _, e1 := syscall.Syscall(procWSAEnumProtocolsW.Addr(), 3, uintptr(unsafe.Pointer(protocols)), uintptr(unsafe.Pointer(protocolBuffer)), uintptr(unsafe.Pointer(bufferLength)))
 	n = int32(r0)
 	if n == -1 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3284,11 +2468,7 @@
 	r0, _, e1 := syscall.Syscall6(procMultiByteToWideChar.Addr(), 6, uintptr(codePage), uintptr(dwFlags), uintptr(unsafe.Pointer(str)), uintptr(nstr), uintptr(unsafe.Pointer(wchar)), uintptr(nwchar))
 	nwrite = int32(r0)
 	if nwrite == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3296,11 +2476,7 @@
 func TranslateName(accName *uint16, accNameFormat uint32, desiredNameFormat uint32, translatedName *uint16, nSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procTranslateNameW.Addr(), 5, uintptr(unsafe.Pointer(accName)), uintptr(accNameFormat), uintptr(desiredNameFormat), uintptr(unsafe.Pointer(translatedName)), uintptr(unsafe.Pointer(nSize)), 0)
 	if r1&0xff == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3308,11 +2484,7 @@
 func GetUserNameEx(nameFormat uint32, nameBuffre *uint16, nSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetUserNameExW.Addr(), 3, uintptr(nameFormat), uintptr(unsafe.Pointer(nameBuffre)), uintptr(unsafe.Pointer(nSize)))
 	if r1&0xff == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3344,11 +2516,7 @@
 func LookupAccountSid(systemName *uint16, sid *SID, name *uint16, nameLen *uint32, refdDomainName *uint16, refdDomainNameLen *uint32, use *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall9(procLookupAccountSidW.Addr(), 7, uintptr(unsafe.Pointer(systemName)), uintptr(unsafe.Pointer(sid)), uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(nameLen)), uintptr(unsafe.Pointer(refdDomainName)), uintptr(unsafe.Pointer(refdDomainNameLen)), uintptr(unsafe.Pointer(use)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3356,11 +2524,7 @@
 func LookupAccountName(systemName *uint16, accountName *uint16, sid *SID, sidLen *uint32, refdDomainName *uint16, refdDomainNameLen *uint32, use *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall9(procLookupAccountNameW.Addr(), 7, uintptr(unsafe.Pointer(systemName)), uintptr(unsafe.Pointer(accountName)), uintptr(unsafe.Pointer(sid)), uintptr(unsafe.Pointer(sidLen)), uintptr(unsafe.Pointer(refdDomainName)), uintptr(unsafe.Pointer(refdDomainNameLen)), uintptr(unsafe.Pointer(use)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3368,11 +2532,7 @@
 func ConvertSidToStringSid(sid *SID, stringSid **uint16) (err error) {
 	r1, _, e1 := syscall.Syscall(procConvertSidToStringSidW.Addr(), 2, uintptr(unsafe.Pointer(sid)), uintptr(unsafe.Pointer(stringSid)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3380,11 +2540,7 @@
 func ConvertStringSidToSid(stringSid *uint16, sid **SID) (err error) {
 	r1, _, e1 := syscall.Syscall(procConvertStringSidToSidW.Addr(), 2, uintptr(unsafe.Pointer(stringSid)), uintptr(unsafe.Pointer(sid)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3398,11 +2554,7 @@
 func CopySid(destSidLen uint32, destSid *SID, srcSid *SID) (err error) {
 	r1, _, e1 := syscall.Syscall(procCopySid.Addr(), 3, uintptr(destSidLen), uintptr(unsafe.Pointer(destSid)), uintptr(unsafe.Pointer(srcSid)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3410,11 +2562,7 @@
 func AllocateAndInitializeSid(identAuth *SidIdentifierAuthority, subAuth byte, subAuth0 uint32, subAuth1 uint32, subAuth2 uint32, subAuth3 uint32, subAuth4 uint32, subAuth5 uint32, subAuth6 uint32, subAuth7 uint32, sid **SID) (err error) {
 	r1, _, e1 := syscall.Syscall12(procAllocateAndInitializeSid.Addr(), 11, uintptr(unsafe.Pointer(identAuth)), uintptr(subAuth), uintptr(subAuth0), uintptr(subAuth1), uintptr(subAuth2), uintptr(subAuth3), uintptr(subAuth4), uintptr(subAuth5), uintptr(subAuth6), uintptr(subAuth7), uintptr(unsafe.Pointer(sid)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3422,11 +2570,7 @@
 func createWellKnownSid(sidType WELL_KNOWN_SID_TYPE, domainSid *SID, sid *SID, sizeSid *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procCreateWellKnownSid.Addr(), 4, uintptr(sidType), uintptr(unsafe.Pointer(domainSid)), uintptr(unsafe.Pointer(sid)), uintptr(unsafe.Pointer(sizeSid)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3440,11 +2584,7 @@
 func FreeSid(sid *SID) (err error) {
 	r1, _, e1 := syscall.Syscall(procFreeSid.Addr(), 1, uintptr(unsafe.Pointer(sid)), 0, 0)
 	if r1 != 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3482,11 +2622,7 @@
 func checkTokenMembership(tokenHandle Token, sidToCheck *SID, isMember *int32) (err error) {
 	r1, _, e1 := syscall.Syscall(procCheckTokenMembership.Addr(), 3, uintptr(tokenHandle), uintptr(unsafe.Pointer(sidToCheck)), uintptr(unsafe.Pointer(isMember)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3494,11 +2630,7 @@
 func OpenProcessToken(process Handle, access uint32, token *Token) (err error) {
 	r1, _, e1 := syscall.Syscall(procOpenProcessToken.Addr(), 3, uintptr(process), uintptr(access), uintptr(unsafe.Pointer(token)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3510,11 +2642,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procOpenThreadToken.Addr(), 4, uintptr(thread), uintptr(access), uintptr(_p0), uintptr(unsafe.Pointer(token)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3522,11 +2650,7 @@
 func ImpersonateSelf(impersonationlevel uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procImpersonateSelf.Addr(), 1, uintptr(impersonationlevel), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3534,11 +2658,7 @@
 func RevertToSelf() (err error) {
 	r1, _, e1 := syscall.Syscall(procRevertToSelf.Addr(), 0, 0, 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3546,11 +2666,7 @@
 func SetThreadToken(thread *Handle, token Token) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetThreadToken.Addr(), 2, uintptr(unsafe.Pointer(thread)), uintptr(token), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3558,11 +2674,7 @@
 func LookupPrivilegeValue(systemname *uint16, name *uint16, luid *LUID) (err error) {
 	r1, _, e1 := syscall.Syscall(procLookupPrivilegeValueW.Addr(), 3, uintptr(unsafe.Pointer(systemname)), uintptr(unsafe.Pointer(name)), uintptr(unsafe.Pointer(luid)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3574,11 +2686,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procAdjustTokenPrivileges.Addr(), 6, uintptr(token), uintptr(_p0), uintptr(unsafe.Pointer(newstate)), uintptr(buflen), uintptr(unsafe.Pointer(prevstate)), uintptr(unsafe.Pointer(returnlen)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3590,11 +2698,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procAdjustTokenGroups.Addr(), 6, uintptr(token), uintptr(_p0), uintptr(unsafe.Pointer(newstate)), uintptr(buflen), uintptr(unsafe.Pointer(prevstate)), uintptr(unsafe.Pointer(returnlen)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3602,11 +2706,7 @@
 func GetTokenInformation(token Token, infoClass uint32, info *byte, infoLen uint32, returnedLen *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procGetTokenInformation.Addr(), 5, uintptr(token), uintptr(infoClass), uintptr(unsafe.Pointer(info)), uintptr(infoLen), uintptr(unsafe.Pointer(returnedLen)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3614,11 +2714,7 @@
 func SetTokenInformation(token Token, infoClass uint32, info *byte, infoLen uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procSetTokenInformation.Addr(), 4, uintptr(token), uintptr(infoClass), uintptr(unsafe.Pointer(info)), uintptr(infoLen), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3626,11 +2722,7 @@
 func DuplicateTokenEx(existingToken Token, desiredAccess uint32, tokenAttributes *SecurityAttributes, impersonationLevel uint32, tokenType uint32, newToken *Token) (err error) {
 	r1, _, e1 := syscall.Syscall6(procDuplicateTokenEx.Addr(), 6, uintptr(existingToken), uintptr(desiredAccess), uintptr(unsafe.Pointer(tokenAttributes)), uintptr(impersonationLevel), uintptr(tokenType), uintptr(unsafe.Pointer(newToken)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3638,11 +2730,7 @@
 func GetUserProfileDirectory(t Token, dir *uint16, dirLen *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetUserProfileDirectoryW.Addr(), 3, uintptr(t), uintptr(unsafe.Pointer(dir)), uintptr(unsafe.Pointer(dirLen)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3651,11 +2739,7 @@
 	r0, _, e1 := syscall.Syscall(procGetSystemDirectoryW.Addr(), 2, uintptr(unsafe.Pointer(dir)), uintptr(dirLen), 0)
 	len = uint32(r0)
 	if len == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3664,11 +2748,7 @@
 	r0, _, e1 := syscall.Syscall(procGetWindowsDirectoryW.Addr(), 2, uintptr(unsafe.Pointer(dir)), uintptr(dirLen), 0)
 	len = uint32(r0)
 	if len == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3677,11 +2757,7 @@
 	r0, _, e1 := syscall.Syscall(procGetSystemWindowsDirectoryW.Addr(), 2, uintptr(unsafe.Pointer(dir)), uintptr(dirLen), 0)
 	len = uint32(r0)
 	if len == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3689,11 +2765,7 @@
 func WTSQueryUserToken(session uint32, token *Token) (err error) {
 	r1, _, e1 := syscall.Syscall(procWTSQueryUserToken.Addr(), 2, uintptr(session), uintptr(unsafe.Pointer(token)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3701,11 +2773,7 @@
 func WTSEnumerateSessions(handle Handle, reserved uint32, version uint32, sessions **WTS_SESSION_INFO, count *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procWTSEnumerateSessionsW.Addr(), 5, uintptr(handle), uintptr(reserved), uintptr(version), uintptr(unsafe.Pointer(sessions)), uintptr(unsafe.Pointer(count)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3773,11 +2841,7 @@
 func initializeSecurityDescriptor(absoluteSD *SECURITY_DESCRIPTOR, revision uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procInitializeSecurityDescriptor.Addr(), 2, uintptr(unsafe.Pointer(absoluteSD)), uintptr(revision), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3785,11 +2849,7 @@
 func getSecurityDescriptorControl(sd *SECURITY_DESCRIPTOR, control *SECURITY_DESCRIPTOR_CONTROL, revision *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procGetSecurityDescriptorControl.Addr(), 3, uintptr(unsafe.Pointer(sd)), uintptr(unsafe.Pointer(control)), uintptr(unsafe.Pointer(revision)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3807,11 +2867,7 @@
 	*daclPresent = _p0 != 0
 	*daclDefaulted = _p1 != 0
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3829,11 +2885,7 @@
 	*saclPresent = _p0 != 0
 	*saclDefaulted = _p1 != 0
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3846,11 +2898,7 @@
 	r1, _, e1 := syscall.Syscall(procGetSecurityDescriptorOwner.Addr(), 3, uintptr(unsafe.Pointer(sd)), uintptr(unsafe.Pointer(owner)), uintptr(unsafe.Pointer(&_p0)))
 	*ownerDefaulted = _p0 != 0
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3863,11 +2911,7 @@
 	r1, _, e1 := syscall.Syscall(procGetSecurityDescriptorGroup.Addr(), 3, uintptr(unsafe.Pointer(sd)), uintptr(unsafe.Pointer(group)), uintptr(unsafe.Pointer(&_p0)))
 	*groupDefaulted = _p0 != 0
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3895,11 +2939,7 @@
 func setSecurityDescriptorControl(sd *SECURITY_DESCRIPTOR, controlBitsOfInterest SECURITY_DESCRIPTOR_CONTROL, controlBitsToSet SECURITY_DESCRIPTOR_CONTROL) (err error) {
 	r1, _, e1 := syscall.Syscall(procSetSecurityDescriptorControl.Addr(), 3, uintptr(unsafe.Pointer(sd)), uintptr(controlBitsOfInterest), uintptr(controlBitsToSet))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3915,11 +2955,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procSetSecurityDescriptorDacl.Addr(), 4, uintptr(unsafe.Pointer(sd)), uintptr(_p0), uintptr(unsafe.Pointer(dacl)), uintptr(_p1), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3935,11 +2971,7 @@
 	}
 	r1, _, e1 := syscall.Syscall6(procSetSecurityDescriptorSacl.Addr(), 4, uintptr(unsafe.Pointer(sd)), uintptr(_p0), uintptr(unsafe.Pointer(sacl)), uintptr(_p1), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3951,11 +2983,7 @@
 	}
 	r1, _, e1 := syscall.Syscall(procSetSecurityDescriptorOwner.Addr(), 3, uintptr(unsafe.Pointer(sd)), uintptr(unsafe.Pointer(owner)), uintptr(_p0))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3967,11 +2995,7 @@
 	}
 	r1, _, e1 := syscall.Syscall(procSetSecurityDescriptorGroup.Addr(), 3, uintptr(unsafe.Pointer(sd)), uintptr(unsafe.Pointer(group)), uintptr(_p0))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -3993,11 +3017,7 @@
 func _convertStringSecurityDescriptorToSecurityDescriptor(str *uint16, revision uint32, sd **SECURITY_DESCRIPTOR, size *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procConvertStringSecurityDescriptorToSecurityDescriptorW.Addr(), 4, uintptr(unsafe.Pointer(str)), uintptr(revision), uintptr(unsafe.Pointer(sd)), uintptr(unsafe.Pointer(size)), 0, 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -4005,11 +3025,7 @@
 func convertSecurityDescriptorToStringSecurityDescriptor(sd *SECURITY_DESCRIPTOR, revision uint32, securityInformation SECURITY_INFORMATION, str **uint16, strLen *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall6(procConvertSecurityDescriptorToStringSecurityDescriptorW.Addr(), 5, uintptr(unsafe.Pointer(sd)), uintptr(revision), uintptr(securityInformation), uintptr(unsafe.Pointer(str)), uintptr(unsafe.Pointer(strLen)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -4017,11 +3033,7 @@
 func makeAbsoluteSD(selfRelativeSD *SECURITY_DESCRIPTOR, absoluteSD *SECURITY_DESCRIPTOR, absoluteSDSize *uint32, dacl *ACL, daclSize *uint32, sacl *ACL, saclSize *uint32, owner *SID, ownerSize *uint32, group *SID, groupSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall12(procMakeAbsoluteSD.Addr(), 11, uintptr(unsafe.Pointer(selfRelativeSD)), uintptr(unsafe.Pointer(absoluteSD)), uintptr(unsafe.Pointer(absoluteSDSize)), uintptr(unsafe.Pointer(dacl)), uintptr(unsafe.Pointer(daclSize)), uintptr(unsafe.Pointer(sacl)), uintptr(unsafe.Pointer(saclSize)), uintptr(unsafe.Pointer(owner)), uintptr(unsafe.Pointer(ownerSize)), uintptr(unsafe.Pointer(group)), uintptr(unsafe.Pointer(groupSize)), 0)
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }
@@ -4029,11 +3041,7 @@
 func makeSelfRelativeSD(absoluteSD *SECURITY_DESCRIPTOR, selfRelativeSD *SECURITY_DESCRIPTOR, selfRelativeSDSize *uint32) (err error) {
 	r1, _, e1 := syscall.Syscall(procMakeSelfRelativeSD.Addr(), 3, uintptr(unsafe.Pointer(absoluteSD)), uintptr(unsafe.Pointer(selfRelativeSD)), uintptr(unsafe.Pointer(selfRelativeSDSize)))
 	if r1 == 0 {
-		if e1 != 0 {
-			err = errnoErr(e1)
-		} else {
-			err = syscall.EINVAL
-		}
+		err = errnoErr(e1)
 	}
 	return
 }