[Midnightbsd-cvs] src [7939] trunk/lib/libc/sys/fcntl.2: document cloexec

[laffer1 at midnightbsd.org]

Revision: 7939
          http://svnweb.midnightbsd.org/src/?rev=7939
Author:   laffer1
Date:     2016-09-14 17:39:27 -0400 (Wed, 14 Sep 2016)
Log Message:
-----------
document cloexec

Modified Paths:
--------------
    trunk/lib/libc/sys/fcntl.2

Modified: trunk/lib/libc/sys/fcntl.2
===================================================================
--- trunk/lib/libc/sys/fcntl.2	2016-09-14 21:36:45 UTC (rev 7938)
+++ trunk/lib/libc/sys/fcntl.2	2016-09-14 21:39:27 UTC (rev 7939)
@@ -28,7 +28,7 @@
 .\"     @(#)fcntl.2	8.2 (Berkeley) 1/12/94
 .\" $MidnightBSD$
 .\"
-.Dd September 28, 2009
+.Dd July 27, 2012
 .Dt FCNTL 2
 .Os
 .Sh NAME
@@ -54,7 +54,7 @@
 .Fn fcntl
 can take an additional third argument
 .Fa "int arg" .
-.Bl -tag -width F_GETOWNX
+.Bl -tag -width F_DUP2FD_CLOEXEC
 .It Dv F_DUPFD
 Return a new descriptor as follows:
 .Pp
@@ -73,23 +73,44 @@
 Same file status flags (i.e., both file descriptors
 share the same file status flags).
 .It
-The close-on-exec flag associated with the new file descriptor
-is set to remain open across
+The close-on-exec flag
+.Dv FD_CLOEXEC
+associated with the new file descriptor is cleared, so the file descriptor is
+to remain open across
 .Xr execve 2
 system calls.
 .El
+.It Dv F_DUPFD_CLOEXEC
+Like
+.Dv F_DUPFD ,
+but the
+.Dv FD_CLOEXEC
+flag associated with the new file descriptor is set, so the file descriptor
+is closed when
+.Xr execve 2
+system call executes.
 .It Dv F_DUP2FD
 It is functionally equivalent to
 .Bd -literal -offset indent
 dup2(fd, arg)
 .Ed
+.It Dv F_DU2PFD_CLOEXEC
+Like
+.Dv F_DUP2FD ,
+but the
+.Dv FD_CLOEXEC
+flag associated with the new file descriptor is set.
 .Pp
 The
 .Dv F_DUP2FD
-constant is not portable, so it should not be used if portability is needed.
+and
+.Dv F_DUP2DF_CLOEXEC
+constants are not portable, so they should not be used if
+portability is needed.
 Use
 .Fn dup2
-instead.
+instead of
+.Dv F_DUP2FD .
 .It Dv F_GETFD
 Get the close-on-exec flag associated with the file descriptor
 .Fa fd