1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
/*
* Copyright (c) 1990, 2010, Oracle and/or its affiliates. All rights reserved.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved. The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/
/*
* users
*/
#include <stdio.h>
#include <sys/types.h>
#include <stdlib.h>
#include <utmpx.h>
#include <string.h>
static char **names;
static char **namp;
static int scmp(const void *p, const void *q);
static void summary(void);
int
main(int argc, char **argv)
{
int nusers = 0;
int bufflen = BUFSIZ;
struct utmpx *utmpx;
if (argc == 2)
if (!utmpxname(argv[1])) {
(void) fprintf(stderr, "Filename is too long\n");
exit(1);
}
names = namp = (char **)realloc((void *)NULL, BUFSIZ * sizeof (char *));
setutxent();
while ((utmpx = getutxent()) != NULL) {
if (utmpx->ut_name[0] == '\0')
continue;
if (utmpx->ut_type != USER_PROCESS)
continue;
if (nonuserx(*utmpx))
continue;
if (nusers == bufflen) {
bufflen *= 2;
names = (char **)realloc(names,
bufflen * sizeof (char *));
namp = names + nusers;
}
*namp++ = strndup(utmpx->ut_name, sizeof (utmpx->ut_name));
nusers++;
}
endutxent();
summary();
return (0);
}
static int
scmp(const void *p, const void *q)
{
return (strcmp((char *)p, (char *)q));
}
static void
summary(void)
{
register char **p;
qsort(names, namp - names, sizeof (names[0]), scmp);
for (p = names; p < namp; p++) {
if (p != names)
(void) putchar(' ');
(void) fputs(*p, stdout);
}
if (namp != names) /* at least one user */
(void) putchar('\n');
}
|
