diff --git a/libc/include/sys/ptrace.h b/libc/include/sys/ptrace.h
index 4b881e7..022fc3a 100644
--- a/libc/include/sys/ptrace.h
+++ b/libc/include/sys/ptrace.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_PTRACE_H_
 #define _SYS_PTRACE_H_
 
@@ -58,8 +59,8 @@
 #define PT_GETSIGINFO PTRACE_GETSIGINFO
 #define PT_SETSIGINFO PTRACE_SETSIGINFO
 
-long ptrace(int, ...);
+long ptrace(int __request, ...);
 
 __END_DECLS
 
-#endif /* _SYS_PTRACE_H_ */
+#endif