all: fix some comments

Change-Id: I7d5bfd4caac63820b26fc3408118c13e74e6448c
Reviewed-on: https://go-review.googlesource.com/c/sys/+/464238
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
diff --git a/plan9/mksyscall.go b/plan9/mksyscall.go
index a5062c2..d7a481f 100644
--- a/plan9/mksyscall.go
+++ b/plan9/mksyscall.go
@@ -55,7 +55,7 @@
 	return strings.ReplaceAll(*tags, ",", " && ")
 }
 
-// plusBuildTags returns build tags in the +build format.
+// buildTags returns build tags in the +build format.
 func buildTags() string {
 	return *tags
 }
diff --git a/unix/syscall_unix.go b/unix/syscall_unix.go
index a386f88..00f0aa3 100644
--- a/unix/syscall_unix.go
+++ b/unix/syscall_unix.go
@@ -578,7 +578,7 @@
 	return UtimesNanoAt(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW)
 }
 
-// emptyIovec reports whether there are no bytes in the slice of Iovec.
+// emptyIovecs reports whether there are no bytes in the slice of Iovec.
 func emptyIovecs(iov []Iovec) bool {
 	for i := range iov {
 		if iov[i].Len > 0 {
diff --git a/unix/timestruct.go b/unix/timestruct.go
index 3d89304..616b1b2 100644
--- a/unix/timestruct.go
+++ b/unix/timestruct.go
@@ -9,7 +9,7 @@
 
 import "time"
 
-// TimespecToNSec returns the time stored in ts as nanoseconds.
+// TimespecToNsec returns the time stored in ts as nanoseconds.
 func TimespecToNsec(ts Timespec) int64 { return ts.Nano() }
 
 // NsecToTimespec converts a number of nanoseconds into a Timespec.