Golang Rich I/O two----version cgo Hello World

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Golang Rich I/O two ----version cgo Hello World

InGolangRich inI/o----UseNTwoHello WorldShow "in a variety ofHello WorldThe wording of this showGolangRich and powerfulI/Ofunction, in addition to aCGOVersion ofHello World。 The following code is derived fromGoSource:

Main.go

Package Mainimport "Stdio" Func Main () {    stdio. Stdout.writestring (stdio. Greeting + "\ n")}

　　

File.go

skip//Copyright Authors the Go. All rights reserved.//Use of this source code are governed by a bsd-style//license so 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" Typefile c.file//Test reference to Library symbol.//Stdout and stderr is too special to be a reliable Test.//var = C.environfunc (f *file) WriteString (s string) { C0/>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)))

　　

Stdio.go

skip//Copyright Authors the Go. All rights reserved.//Use of this source code are governed by a bsd-style//license so can be found in the license file. Package stdio/* #include <stdio.h>//on MinGW, stderr and stdout is defined as &_iob[fileno]//on NetBSD, they a Re defined as &__sf[fileno]//and CGO doesn ' t recognize them, so write a function to get them,//instead of depending On internals of LIBC implementation. FILE *getstdout (void) {return stdout;} FILE *getstderr (void) {return stderr;} */import "C" var Stdout = (*file) (C.getstdout ()) var Stderr = (*file) (C.getstderr ())

　　

GoProgram can be passedCGOTool makes it very easy to invokeCFunction. AboutGoCallC + +OrC + +CallGoThe program can refer to the previous series of essays "C + +CallGolangandcalling C + + from Golang with swig---windows DLLs》