61 lines
1.2 KiB
C
61 lines
1.2 KiB
C
/*++
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/* NAME
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/* close_on_exec 3
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/* SUMMARY
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/* set/clear close-on-exec flag
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/* SYNOPSIS
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/* #include <iostuff.h>
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/*
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/* int close_on_exec(int fd, int on)
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/* DESCRIPTION
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/* the \fIclose_on_exec\fR() function manipulates the close-on-exec
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/* flag for the specified open file, and returns the old setting.
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/*
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/* Arguments:
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/* .IP fd
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/* A file descriptor.
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/* .IP on
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/* Use CLOSE_ON_EXEC or PASS_ON_EXEC.
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/* DIAGNOSTICS
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/* All errors are fatal.
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/* LICENSE
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/* .ad
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/* .fi
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/* The Secure Mailer license must be distributed with this software.
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/* AUTHOR(S)
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/* Wietse Venema
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/* IBM T.J. Watson Research
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/* P.O. Box 704
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/* Yorktown Heights, NY 10598, USA
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/*--*/
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/* System interfaces. */
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#include <sys_defs.h>
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#include <fcntl.h>
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/* Utility library. */
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#include "msg.h"
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/* Application-specific. */
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#include "iostuff.h"
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#define PATTERN FD_CLOEXEC
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/* close_on_exec - set/clear close-on-exec flag */
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int close_on_exec(fd, on)
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int fd;
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int on;
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{
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int flags;
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if ((flags = fcntl(fd, F_GETFD, 0)) < 0)
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msg_fatal("fcntl: get flags: %m");
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if (fcntl(fd, F_SETFD, on ? flags | PATTERN : flags & ~PATTERN) < 0)
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msg_fatal("fcntl: set close-on-exec flag %s: %m", on ? "on" : "off");
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return ((flags & PATTERN) != 0);
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}
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