System Libraries

Link C system libraries.

build.zig

const std = @import("std");
const buildx = @import("buildx");

pub fn build(b: *std.Build) void {
    _ = buildx.project(b, .{
        .name = "syslibapp",
        .root = "src/main.zig",
        .link = .{
            .system_libs = &.{
                .{ .name = "m", .needs_libc = true },
            },
        },
        .install = true,
    });
}

src/main.zig

const std = @import("std");

extern "c" fn sin(f64) f64;

pub fn main() void {
    const x = sin(1.0);
    std.debug.print("sin(1.0) = {d}\n", .{x});
}

Build & Run

zig build
zig-out/bin/syslibapp

Output:

sin(1.0) = 0.8414709848078965

What Happens

• needs_libc = true links libc automatically
• The sin function comes from libm, linked via libc