projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 76f20214 | 1 | static char *sccsid = "@(#)mesg.c 4.2 (Berkeley) %G%"; |
| 69d8f2f4 BJ |
2 | /* |
| 3 | * mesg -- set current tty to accept or | |
| 4 | * forbid write permission. | |
| 5 | * | |
| 6 | * mesg [y] [n] | |
| 7 | * y allow messages | |
| 8 | * n forbid messages | |
| 9 | */ | |
| 10 | ||
| 11 | #include <stdio.h> | |
| 12 | #include <sys/types.h> | |
| 13 | #include <sys/stat.h> | |
| 14 | ||
| 15 | struct stat sbuf; | |
| 16 | ||
| 17 | char *tty; | |
| 18 | char *ttyname(); | |
| 19 | ||
| 20 | main(argc, argv) | |
| 21 | char *argv[]; | |
| 22 | { | |
| 23 | int r=0; | |
| 24 | tty = ttyname(2); | |
| 25 | if (tty == 0) | |
| 26 | exit(13); | |
| 27 | if(stat(tty, &sbuf) < 0) error("cannot stat"); | |
| 28 | if(argc < 2) { | |
| 29 | if(sbuf.st_mode & 02) | |
| 30 | fprintf(stderr,"is y\n"); | |
| 31 | else { r=1; | |
| 32 | fprintf(stderr,"is n\n"); | |
| 33 | } | |
| 34 | } else switch(*argv[1]) { | |
| 35 | case 'y': | |
| 76f20214 | 36 | newmode(sbuf.st_mode|022); break; |
| 69d8f2f4 BJ |
37 | |
| 38 | case 'n': | |
| 76f20214 | 39 | newmode(sbuf.st_mode&~022); r=1; break; |
| 69d8f2f4 BJ |
40 | |
| 41 | default: | |
| 42 | error("usage: mesg [y] [n]"); | |
| 43 | } | |
| 44 | exit(r); | |
| 45 | } | |
| 46 | ||
| 47 | error(s) | |
| 48 | char *s; | |
| 49 | { | |
| 50 | fprintf(stderr,"mesg: %s\n",s); | |
| 51 | exit(-1); | |
| 52 | } | |
| 53 | ||
| 54 | newmode(m) | |
| 55 | { | |
| 56 | if(chmod(tty,m)<0) | |
| 57 | error("cannot change mode"); | |
| 58 | } |