diff --git a/man2/execve.2 b/man2/execve.2
index 19ea4cee7..4f4d092e2 100644
--- a/man2/execve.2
+++ b/man2/execve.2
@@ -65,7 +65,8 @@ If the current program is being ptraced, a \fBSIGTRAP\fP is sent to it
 after a successful \fBexecve()\fP.
 
 If the set-uid bit is set on the program file pointed to by
-\fIfilename\fP the effective user ID of the calling process is changed
+\fIfilename\fP, and the calling process is not being ptraced,
+then the effective user ID of the calling process is changed
 to that of the owner of the program file.  Similarly, when the set-gid
 bit of the program file is set the effective group ID of the calling
 process is set to the group of the program file.
@@ -210,6 +211,7 @@ Since Unix V7 both are NULL.
 .BR chmod (2),
 .BR fork (2),
 .BR path_resolution (2),
+.BR ptrace (2),
 .BR execl (3),
 .BR environ (5),
 .BR ld.so (8)