Using a c shared library from zig
Using a c library from zig is quite easy. The zig compiler understands c code so no FFI required.
Create a standard zig project
$ zig init-exe
Find a library and function(s) you would like to use
$ ls /lib/
As an example I will use libc and the simplest function I can think to use is:
$ nm -C -A /lib/libc.so.6 | grep " printf"
/lib/libc.so.6:0000000000058230 T printf
Link the library in your build.zig file
$ git diff build.zig
diff --git a/build.zig b/build.zig
index 0e4f4b7..66343d9 100644
--- a/build.zig
+++ b/build.zig
@@ -12,6 +12,7 @@ pub fn build(b: *std.build.Builder) void {
const mode = b.standardReleaseOptions();
const exe = b.addExecutable("c_lib_test", "src/main.zig");
+ exe.linkSystemLibrary("c");
exe.setTarget(target);
exe.setBuildMode(mode);
exe.install();
Import and call library in your zig code
The import is done with two builtin functions
const c = @cImport({
@cInclude("stdio.h");
});
Now all functions in stdio resides under the the const c and can be called like so:
c.printf("Hello world of C!");
Thats it, here is the full program
const c = @cImport({
@cInclude("stdio.h");
});
pub fn main() void {
_ = c.printf("Hello world of C!");
}
$ zig build run
Hello world of C!