| 1 | /* |
| 2 | * users |
| 3 | */ |
| 4 | char *malloc(); |
| 5 | |
| 6 | #include <stdio.h> |
| 7 | #include <utmp.h> |
| 8 | |
| 9 | struct utmp utmp; |
| 10 | |
| 11 | main(argc, argv) |
| 12 | char **argv; |
| 13 | { |
| 14 | register char *tp, *s; |
| 15 | register FILE *fi; |
| 16 | |
| 17 | s = "/etc/utmp"; |
| 18 | if(argc == 2) |
| 19 | s = argv[1]; |
| 20 | if ((fi = fopen(s, "r")) == NULL) { |
| 21 | puts("who: cannot open utmp"); |
| 22 | exit(1); |
| 23 | } |
| 24 | while (fread((char *)&utmp, sizeof(utmp), 1, fi) == 1) { |
| 25 | if(utmp.ut_name[0] == '\0') |
| 26 | continue; |
| 27 | putline(); |
| 28 | } |
| 29 | summary(); |
| 30 | } |
| 31 | |
| 32 | char *names[128]; |
| 33 | char **namp = names; |
| 34 | putline() |
| 35 | { |
| 36 | char temp[9]; |
| 37 | strncpy(temp, utmp.ut_name, 8); |
| 38 | *namp = malloc(strlen(temp) + 1); |
| 39 | strcpy(*namp++, temp); |
| 40 | } |
| 41 | |
| 42 | scmp(p, q) |
| 43 | char **p, **q; |
| 44 | { |
| 45 | return(strcmp(*p, *q)); |
| 46 | } |
| 47 | summary() |
| 48 | { |
| 49 | register char **p; |
| 50 | |
| 51 | qsort(names, namp - names, sizeof names[0], scmp); |
| 52 | for (p=names; p < namp; p++) { |
| 53 | if (p != names) |
| 54 | printf(" "); |
| 55 | printf("%s", *p); |
| 56 | } |
| 57 | printf("\n"); |
| 58 | } |