| 1 | #include <stdio.h> |
| 2 | #include <utmp.h> |
| 3 | #define USERS 50 |
| 4 | |
| 5 | char mesg[3000]; |
| 6 | int msize; |
| 7 | struct utmp utmp[USERS]; |
| 8 | char *strcpy(); |
| 9 | char *strcat(); |
| 10 | |
| 11 | main(argc, argv) |
| 12 | char *argv[]; |
| 13 | { |
| 14 | register i; |
| 15 | register struct utmp *p; |
| 16 | FILE *f; |
| 17 | |
| 18 | if((f = fopen("/etc/utmp", "r")) == NULL) { |
| 19 | fprintf(stderr, "Cannot open /etc/utmp\n"); |
| 20 | exit(1); |
| 21 | } |
| 22 | fread((char *)utmp, sizeof(struct utmp), USERS, f); |
| 23 | fclose(f); |
| 24 | f = stdin; |
| 25 | if(argc >= 2) { |
| 26 | if((f = fopen(argv[1], "r")) == NULL) { |
| 27 | fprintf(stderr,"Cannot open %s\n", argv[1]); |
| 28 | exit(1); |
| 29 | } |
| 30 | } |
| 31 | while((i = getc(f)) != EOF) mesg[msize++] = i; |
| 32 | fclose(f); |
| 33 | for(i=0; i<USERS; i++) { |
| 34 | p = &utmp[i]; |
| 35 | if(p->ut_name[0] == 0) |
| 36 | continue; |
| 37 | sleep(1); |
| 38 | sendmes(p->ut_line); |
| 39 | } |
| 40 | exit(0); |
| 41 | } |
| 42 | |
| 43 | sendmes(tty) |
| 44 | char *tty; |
| 45 | { |
| 46 | register i; |
| 47 | char t[50], buf[BUFSIZ]; |
| 48 | FILE *f; |
| 49 | |
| 50 | i = fork(); |
| 51 | if(i == -1) { |
| 52 | fprintf(stderr, "Try again\n"); |
| 53 | return; |
| 54 | } |
| 55 | if(i) |
| 56 | return; |
| 57 | strcpy(t, "/dev/"); |
| 58 | strcat(t, tty); |
| 59 | |
| 60 | if((f = fopen(t, "w")) == NULL) { |
| 61 | fprintf(stderr,"cannot open %s\n", t); |
| 62 | exit(1); |
| 63 | } |
| 64 | setbuf(f, buf); |
| 65 | fprintf(f, "\a\a\aBroadcast Message ...\n\n"); |
| 66 | fwrite(mesg, msize, 1, f); |
| 67 | exit(0); |
| 68 | } |