freebsd-nq/usr.bin/users/users.c

117 lines
3.2 KiB
C

/*
* Copyright (c) 1980, 1987, 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1980, 1987, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)users.c 8.1 (Berkeley) 6/6/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
#include <sys/param.h>
#include <sys/types.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <utmpx.h>
typedef char namebuf[sizeof(((struct utmpx *)0)->ut_user) + 1];
int scmp(const void *, const void *);
static void usage(void);
int
main(int argc, char **argv)
{
namebuf *names = NULL;
int ncnt = 0;
int nmax = 0;
int cnt;
struct utmpx *ut;
int ch;
while ((ch = getopt(argc, argv, "")) != -1)
switch(ch) {
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
setutxent();
while ((ut = getutxent()) != NULL) {
if (ut->ut_type != USER_PROCESS)
continue;
if (ncnt >= nmax) {
nmax += 32;
names = realloc(names, sizeof(*names) * nmax);
if (!names) {
errx(1, "realloc");
/* NOTREACHED */
}
}
(void)strlcpy(names[ncnt], ut->ut_user, sizeof(*names));
++ncnt;
}
endutxent();
if (ncnt > 0) {
qsort(names, ncnt, sizeof(namebuf), scmp);
(void)printf("%s", names[0]);
for (cnt = 1; cnt < ncnt; ++cnt)
if (strcmp(names[cnt], names[cnt - 1]) != 0)
(void)printf(" %s", names[cnt]);
(void)printf("\n");
}
exit(0);
}
static void
usage(void)
{
(void)fprintf(stderr, "usage: users\n");
exit(1);
}
int
scmp(const void *p, const void *q)
{
return (strcmp(p, q));
}