Annotation of src/usr.bin/users/users.c, Revision 1.3
1.3 ! millert 1: /* $OpenBSD: users.c,v 1.2 1996/06/26 05:42:20 deraadt Exp $ */
1.1 deraadt 2: /* $NetBSD: users.c,v 1.5 1994/12/20 15:58:19 jtc Exp $ */
3:
4: /*
5: * Copyright (c) 1980, 1987, 1993
6: * The Regents of the University of California. All rights reserved.
7: *
8: * Redistribution and use in source and binary forms, with or without
9: * modification, are permitted provided that the following conditions
10: * are met:
11: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
13: * 2. Redistributions in binary form must reproduce the above copyright
14: * notice, this list of conditions and the following disclaimer in the
15: * documentation and/or other materials provided with the distribution.
16: * 3. All advertising materials mentioning features or use of this software
17: * must display the following acknowledgement:
18: * This product includes software developed by the University of
19: * California, Berkeley and its contributors.
20: * 4. Neither the name of the University nor the names of its contributors
21: * may be used to endorse or promote products derived from this software
22: * without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34: * SUCH DAMAGE.
35: */
36:
37: #ifndef lint
38: static char copyright[] =
39: "@(#) Copyright (c) 1980, 1987, 1993\n\
40: The Regents of the University of California. All rights reserved.\n";
41: #endif /* not lint */
42:
43: #ifndef lint
44: #if 0
45: static char sccsid[] = "@(#)users.c 8.1 (Berkeley) 6/6/93";
46: #endif
1.3 ! millert 47: static char rcsid[] = "$OpenBSD: users.c,v 1.2 1996/06/26 05:42:20 deraadt Exp $";
1.1 deraadt 48: #endif /* not lint */
49:
50: #include <sys/types.h>
51: #include <utmp.h>
52: #include <stdio.h>
53: #include <stdlib.h>
54: #include <string.h>
55: #include <err.h>
56:
57: typedef char namebuf[UT_NAMESIZE];
58:
59: int scmp __P((const void *, const void *));
60:
61: int
62: main(argc, argv)
63: int argc;
64: char **argv;
65: {
66: namebuf *names = NULL;
67: register int ncnt = 0;
68: register int nmax = 0;
69: int cnt;
70: struct utmp utmp;
71: int ch;
72:
1.3 ! millert 73: while ((ch = getopt(argc, argv, "")) != -1)
1.1 deraadt 74: switch(ch) {
75: case '?':
76: default:
77: (void)fprintf(stderr, "usage: users\n");
78: exit(1);
79: }
80: argc -= optind;
81: argv += optind;
82:
83: if (!freopen(_PATH_UTMP, "r", stdin)) {
84: err(1, "can't open %s", _PATH_UTMP);
85: /* NOTREACHED */
86: }
87:
88: while (fread((char *)&utmp, sizeof(utmp), 1, stdin) == 1) {
89: if (*utmp.ut_name) {
90: if (ncnt >= nmax) {
91: nmax += 32;
92: names = realloc(names,
93: sizeof (*names) * nmax);
94:
95: if (!names) {
96: err(1, NULL);
97: /* NOTREACHED */
98: }
99: }
100:
101: (void)strncpy(names[ncnt], utmp.ut_name, UT_NAMESIZE);
102: ++ncnt;
103: }
104: }
105:
106: if (ncnt) {
107: qsort(names, ncnt, UT_NAMESIZE, scmp);
108: (void)printf("%.*s", UT_NAMESIZE, names[0]);
109: for (cnt = 1; cnt < ncnt; ++cnt)
110: if (strncmp(names[cnt], names[cnt - 1], UT_NAMESIZE))
111: (void)printf(" %.*s", UT_NAMESIZE, names[cnt]);
112: (void)printf("\n");
113: }
114: exit(0);
115: }
116:
117: int
118: scmp(p, q)
119: const void *p, *q;
120: {
121: return(strncmp((char *) p, (char *) q, UT_NAMESIZE));
122: }