| // Copyright 2009 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| /* |
| A trivial example of wrapping a C library in Go. |
| For a more complex example and explanation, |
| see ../gmp/gmp.go. |
| */ |
| |
| package stdio |
| |
| /* |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <sys/stat.h> |
| #include <errno.h> |
| |
| char* greeting = "hello, world"; |
| */ |
| import "C" |
| import "unsafe" |
| |
| type File C.FILE |
| |
| var Stdout = (*File)(C.stdout) |
| var Stderr = (*File)(C.stderr) |
| |
| // Test reference to library symbol. |
| // Stdout and stderr are too special to be a reliable test. |
| //var = C.environ |
| |
| func (f *File) WriteString(s string) { |
| p := C.CString(s) |
| C.fputs(p, (*C.FILE)(f)) |
| C.free(unsafe.Pointer(p)) |
| f.Flush() |
| } |
| |
| func (f *File) Flush() { |
| C.fflush((*C.FILE)(f)) |
| } |
| |
| var Greeting = C.GoString(C.greeting) |
| var Gbytes = C.GoBytes(unsafe.Pointer(C.greeting), C.int(len(Greeting))) |