使用CGO输出helloworld
本人windows版本
go version go1.18.3 windows/amd64
dir 目录: D:\cgo\main
Mode LastWriteTime Length Name
---- ------------- ------ ----
d----- 2023/7/19 21:59 .idea
-a---- 2023/7/19 22:18 1960 first.go
-a---- 2023/7/19 22:03 72 hello.c
-a---- 2023/7/19 22:03 101 hello.cpp
-a---- 2023/7/19 22:07 204 hello.go
-a---- 2023/7/19 22:10 284 hello.h
-a---- 2023/7/19 22:11 6008785 main.exe
first.go
package main
//简单的说，把下面注释的内容写在注释里面显然是比较麻烦的。所有简便起见，把注释的内容写在hello.h里面，然后只引入一个hello.h就好了。
/*
#include<hello.h>
//#include<stdio.h>
//有没有static并不影响,也不需要大小写
//static void sayHello(const char* s) {
// puts(s);
//}
//write by c
//void sayHelloByC(const char* s);
//write by c++
//void sayHelloByCpp(const char* s);
//void sayHelloByGo(char* s);
*/
import "C"
import "fmt"
func main() {
//println("hello world")
C.puts(C.CString("print hello by c.puts\n"))
C.sayHello(C.CString("this is hello\n")) //直接写一个static函数
C.sayHelloByC(C.CString("this is hello from c file\n")) //在这里定义函数，用C实现
C.sayHelloByCpp(C.CString("this is hello from c++ file")) //在这里定义函数，用C++实现
C.sayHelloUseGo(C.CString("this is hello from go file\n")) //一个头文件，用go语言实现功能
C.sayHelloByGo(C.CString("this is hello from go file too\n"))
sayHelloUseGo(C.CString("just call from go\n"))
sayHelloByGo(C.CString("just call from go too"))
}
hello.h
void sayHelloUseGo(char* s);
#include<stdio.h>
//有没有static并不影响,也不需要大小写
static void sayHello(const char* s) {
puts(s);
}
//write by c
void sayHelloByC(const char* s);
//write by c++
void sayHelloByCpp(const char* s);
void sayHelloByGo(char* s);
hello.go
package main
import "C"
import "fmt"
//export sayHelloUseGo
func sayHelloUseGo(s *C.char) {
fmt.Print(C.GoString(s))
}
//export sayHelloByGo
func sayHelloByGo(s *C.char) {
fmt.Print(C.GoString(s))
}
hello.c
#include <stdio.h>
void sayHelloByC(const char* s) {
puts(s);
}
hello.cpp
#include<iostream>
extern "C" void sayHelloByCpp(const char* s) {
std::cout<<s<<std::endl;
}
go run .
或者
go build
执行结果
print hello by c.puts
this is hello
this is hello from c file
this is hello from c++ file
this is hello from go file
this is hello from go file too
just call from go
just call from go too
编程语言之间的相互调用显然是非常方便的，不用再重复开发，这里只是简单举例使用cgo进行输出字符串，至于其他的数据类型，也是大差不差的。