[src/trunk]: src/lib/libc/sys Document PTRACE_POSIX_SPAWN in man-page

[kamil <kamil%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2f54a874dcfa
branches:  trunk
changeset: 841977:2f54a874dcfa
user:      kamil <kamil%NetBSD.org@localhost>
date:      Tue Jun 11 23:27:46 2019 +0000

description:
Document PTRACE_POSIX_SPAWN in man-page

diffstat:

 lib/libc/sys/ptrace.2 |  28 +++++++++++++++++++++-------
 1 files changed, 21 insertions(+), 7 deletions(-)

diffs (57 lines):

diff -r c7ca79efcd8b -r 2f54a874dcfa lib/libc/sys/ptrace.2
--- a/lib/libc/sys/ptrace.2     Tue Jun 11 23:20:18 2019 +0000
+++ b/lib/libc/sys/ptrace.2     Tue Jun 11 23:27:46 2019 +0000
@@ -1,7 +1,7 @@
-.\"    $NetBSD: ptrace.2,v 1.70 2019/05/25 04:25:14 kamil Exp $
+.\"    $NetBSD: ptrace.2,v 1.71 2019/06/11 23:27:46 kamil Exp $
 .\"
 .\" This file is in the public domain.
-.Dd May 25, 2019
+.Dd June 12, 2019
 .Dt PTRACE 2
 .Os
 .Sh NAME
@@ -458,17 +458,16 @@
 Report thread birth.
 .It PTRACE_LWP_EXIT
 Report thread termination.
+.It PTRACE_POSIX_SPAWN
+Report posix_spawn(3).
 .El
 .Pp
 The
 .Xr fork 2
 and
 .Xr vfork 2
-events can occur with similar operations,
-like
-.Xr clone 2
-or
-.Xr posix_spawn 3 .
+events can occur with
+.Xr clone 2 .
 The
 .Dv PTRACE_FORK
 value means that process gives birth to its child
@@ -489,6 +488,21 @@
 .Dv PTRACE_VFORK_DONE
 event can be used to report unblocking of the parent.
 .Pp
+The
+.Xr posix_spawn 3
+operation implements
+.Xr vfork 2
+and
+.Xr exec 3
+as a single syscall in the kernel.
+The
+.Dv PTRACE_POSIX_SPAWN
+event semantics are the same as
+.Dv PTRACE_FORK ,
+but the child is reported with implied
+.Xr exec 3
+operation.
+.Pp
 A pointer to this structure is passed in
 .Fa addr .
 The