How Can I Integrate Go Code into My Existing C Project?

Integrating Go Code into an Existing C Project

Question:
Is it possible to call Go code from a C program, and if so, how can this be achieved?

Answer:
Yes, Go 1.5 introduced the -buildmode=c-archive mode, which allows Go code to be compiled into an archive suitable for linking into C programs. To integrate Go code into an existing C project:

1. Mark Functions for Export:

   • Functions intended to be called from C must be marked with //export comments in the Go code.
   • Ensure the Go package containing these functions is named main.
   • Include a function named main, even if it is empty.
   • Import the C package.

2. Compile Go Archive:

   • Compile the Go code into a C-callable static library using the following command:

     go build -buildmode=c-archive foo.go

   • This will generate an archive and a header file (e.g., foo.a and foo.h).

3. Link C Program:

   • In the C program, include the generated header file:

     #include "foo.h"

   • Link against the Go archive using the -pthread option:

     gcc -pthread foo.c foo.a -o foo

   • This will allow the C program to call the exported Go functions.

Example:

Consider the following Go code (foo.go):

package main

import "C"
import "fmt"

//export PrintInt
func PrintInt(x int) {
    fmt.Println(x)
}

func main() {}

Compile it into an archive:

go build -buildmode=c-archive foo.go

Then, in a C program (foo.c):

#include "foo.h"

int main(int argc, char **argv) {
    PrintInt(42);
    return 0;
}

Compile it:

gcc -pthread foo.c foo.a -o foo

Running foo will print "42".

The above is the detailed content of How Can I Integrate Go Code into My Existing C Project?. For more information, please follow other related articles on the PHP Chinese website!