-#ifndef lint
-static char *sccsid = "@(#)who.c 4.5 (Berkeley) %G%";
-#endif
/*
- * who
+ * Copyright (c) 1989 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Michael Fischbein.
+ *
+ * Redistribution and use in source and binary forms are permitted provided
+ * that: (1) source distributions retain this entire copyright notice and
+ * comment, and (2) distributions including binaries display the following
+ * acknowledgement: ``This product includes software developed by the
+ * University of California, Berkeley and its contributors'' in the
+ * documentation or other materials provided with the distribution and in
+ * all advertising materials mentioning features or use of this software.
+ * 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
-#include <stdio.h>
-#include <utmp.h>
-#include <pwd.h>
-#include <ctype.h>
-
-#define NMAX sizeof(utmp.ut_name)
-#define LMAX sizeof(utmp.ut_line)
-#define HMAX sizeof(utmp.ut_host)
+#ifndef lint
+char copyright[] =
+"@(#) Copyright (c) 1989 The Regents of the University of California.\n\
+ All rights reserved.\n";
+#endif /* not lint */
-struct utmp utmp;
-struct passwd *pw;
-struct passwd *getpwuid();
-char hostname[32];
+#ifndef lint
+static char sccsid[] = "@(#)who.c 5.11 (Berkeley) 6/1/90";
+#endif /* not lint */
-char *ttyname(), *rindex(), *ctime(), *strcpy();
+#include <sys/types.h>
+#include <sys/file.h>
+#include <sys/time.h>
+#include <pwd.h>
+#include <utmp.h>
+#include <stdio.h>
main(argc, argv)
int argc;
char **argv;
{
- register char *tp, *s;
- register FILE *fi;
- extern char _sobuf[];
+ register char *p;
+ struct utmp usr;
+ struct passwd *pw;
+ FILE *ufp, *file();
+ char *t, *rindex(), *strcpy(), *strncpy(), *ttyname();
+ time_t time();
- setbuf(stdout, _sobuf);
- s = "/etc/utmp";
- if(argc == 2)
- s = argv[1];
- if (argc == 3) {
- tp = ttyname(0);
- if (tp)
- tp = rindex(tp, '/') + 1;
- else { /* no tty - use best guess from passwd file */
- pw = getpwuid(getuid());
- strcpy(utmp.ut_name, pw?pw->pw_name: "?");
- strcpy(utmp.ut_line, "tty??");
- time(&utmp.ut_time);
- putline();
- exit(0);
- }
- }
- if ((fi = fopen(s, "r")) == NULL) {
- puts("who: cannot open utmp");
+ switch (argc) {
+ case 1: /* who */
+ ufp = file(_PATH_UTMP);
+ /* only entries with both name and line fields */
+ while (fread((char *)&usr, sizeof(usr), 1, ufp) == 1)
+ if (*usr.ut_name && *usr.ut_line)
+ output(&usr);
+ break;
+ case 2: /* who utmp_file */
+ ufp = file(argv[1]);
+ /* all entries */
+ while (fread((char *)&usr, sizeof(usr), 1, ufp) == 1)
+ output(&usr);
+ break;
+ case 3: /* who am i */
+ ufp = file(_PATH_UTMP);
+
+ /* search through the utmp and find an entry for this tty */
+ if (p = ttyname(0)) {
+ /* strip any directory component */
+ if (t = rindex(p, '/'))
+ p = t + 1;
+ while (fread((char *)&usr, sizeof(usr), 1, ufp) == 1)
+ if (usr.ut_name && !strcmp(usr.ut_line, p)) {
+ output(&usr);
+ exit(0);
+ }
+ /* well, at least we know what the tty is */
+ (void)strncpy(usr.ut_line, p, UT_LINESIZE);
+ } else
+ (void)strcpy(usr.ut_line, "tty??");
+ pw = getpwuid(getuid());
+ (void)strncpy(usr.ut_name, pw ? pw->pw_name : "?", UT_NAMESIZE);
+ (void)time(&usr.ut_time);
+ *usr.ut_host = '\0';
+ output(&usr);
+ break;
+ default:
+ (void)fprintf(stderr, "usage: who [ file ]\n who am i\n");
exit(1);
}
- while (fread((char *)&utmp, sizeof(utmp), 1, fi) == 1) {
- if (argc == 3) {
- gethostname(hostname, sizeof (hostname));
- if (strcmp(utmp.ut_line, tp))
- continue;
- printf("%s!", hostname);
- putline();
- exit(0);
- }
- if (utmp.ut_name[0] == '\0' && argc == 1)
- continue;
- putline();
- }
+ exit(0);
}
-putline()
+output(up)
+ struct utmp *up;
{
- register char *cbuf;
+ char *ctime();
+
+ (void)printf("%-*.*s %-*.*s", UT_NAMESIZE, UT_NAMESIZE, up->ut_name,
+ UT_LINESIZE, UT_LINESIZE, up->ut_line);
+ (void)printf("%.12s", ctime(&up->ut_time) + 4);
+ if (*up->ut_host)
+ printf("\t(%.*s)", UT_HOSTSIZE, up->ut_host);
+ (void)putchar('\n');
+}
- printf("%-*.*s %-*.*s",
- NMAX, NMAX, utmp.ut_name,
- LMAX, LMAX, utmp.ut_line);
- cbuf = ctime(&utmp.ut_time);
- printf("%.12s", cbuf+4);
- if (utmp.ut_host[0])
- printf("\t(%.*s)", HMAX, utmp.ut_host);
- putchar('\n');
+FILE *
+file(name)
+ char *name;
+{
+ extern int errno;
+ FILE *ufp;
+ char *strerror();
+
+ if (!(ufp = fopen(name, "r"))) {
+ (void)fprintf(stderr, "who: %s: %s.\n", name, strerror(errno));
+ exit(1);
+ }
+ return(ufp);
}