diff --git a/lib/std/c.zig b/lib/std/c.zig
index bbc32cf351..aa50fff90e 100644
--- a/lib/std/c.zig
+++ b/lib/std/c.zig
@@ -340,3 +340,5 @@ pub extern "c" fn sync() void;
 pub extern "c" fn syncfs(fd: c_int) c_int;
 pub extern "c" fn fsync(fd: c_int) c_int;
 pub extern "c" fn fdatasync(fd: c_int) c_int;
+
+pub extern "c" fn prctl(option: c_int, ...) c_int;