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/* $OpenBSD: fcntl_dup.c,v 1.3 2017/07/27 10:42:24 bluhm Exp $ */
/*
* Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <err.h>
#include <fcntl.h>
int
main(int argc, char *argv[])
{
int orgfd, fd1, fd2;
char temp[] = "/tmp/dup2XXXXXXXXX";
if ((orgfd = mkstemp(temp)) < 0)
err(1, "mkstemp");
remove(temp);
if (ftruncate(orgfd, 1024) != 0)
err(1, "ftruncate");
if ((fd1 = dup(orgfd)) < 0)
err(1, "dup");
/* Set close-on-exec */
if (fcntl(fd1, F_SETFD, 1) != 0)
err(1, "fcntl(F_SETFD)");
if ((fd2 = fcntl(fd1, F_DUPFD, 0)) < 0)
err(1, "fcntl(F_DUPFD)");
/* Test 2: Was close-on-exec cleared? */
if (fcntl(fd2, F_GETFD) != 0)
errx(1, "fcntl(F_DUPFD) didn't clear close-on-exec");
return 0;
}
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