diff --git a/libc/include/sys/ptrace.h b/libc/include/sys/ptrace.h
index 022fc3a..66b30a1 100644
--- a/libc/include/sys/ptrace.h
+++ b/libc/include/sys/ptrace.h
@@ -59,7 +59,7 @@
 #define PT_GETSIGINFO PTRACE_GETSIGINFO
 #define PT_SETSIGINFO PTRACE_SETSIGINFO
 
-long ptrace(int __request, ...);
+long ptrace(int __op, ...);
 
 __END_DECLS