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/*
* $OpenBSD: readlink.c,v 1.26 2015/10/07 14:10:50 deraadt Exp $
*
* Copyright (c) 1997
* Kenneth Stailey (hereinafter referred to as the author)
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static void usage(void);
int
main(int argc, char *argv[])
{
char buf[PATH_MAX];
int n, ch, nflag = 0, fflag = 0;
extern int optind;
if (tame("stdio rpath", NULL) == -1)
err(1, "tame");
while ((ch = getopt(argc, argv, "fn")) != -1)
switch (ch) {
case 'f':
fflag = 1;
break;
case 'n':
nflag = 1;
break;
default:
usage();
}
argc -= optind;
argv += optind;
if (argc != 1)
usage();
n = strlen(argv[0]);
if (n > PATH_MAX - 1) {
fprintf(stderr,
"readlink: filename longer than PATH_MAX-1 (%d)\n",
PATH_MAX - 1);
exit(1);
}
if (fflag) {
if (realpath(argv[0], buf) == NULL)
err(1, "%s", argv[0]);
} else {
if ((n = readlink(argv[0], buf, sizeof buf-1)) < 0)
exit(1);
buf[n] = '\0';
}
printf("%s", buf);
if (!nflag)
putchar('\n');
exit(0);
}
static void
usage(void)
{
(void)fprintf(stderr, "usage: readlink [-fn] file\n");
exit(1);
}
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