static char *sccsid ="@(#)biff.c 4.1 (Berkeley) 10/18/80"; /* * biff */ #include <sys/types.h> #include <stat.h> #include <stdio.h> char *ttyname(); main(argc, argv) int argc; char **argv; { char *cp = ttyname(2); struct stat stb; argc--, argv++; if (cp == 0) fprintf(stderr, "Where are you?\n"), exit(1); if (stat(cp, &stb) < 0) perror(cp), exit(1); if (argc == 0) { printf("is %s\n", stb.st_mode&0100 ? "y" : "n"); exit((stb.st_mode&0100) ? 0 : 1); } switch (argv[0][0]) { case 'y': if (chmod(cp, stb.st_mode|0100) < 0) perror(cp); break; case 'n': if (chmod(cp, stb.st_mode&~0100) < 0) perror(cp); break; default: fprintf(stderr, "usage: biff [y] [n]\n"); } exit((stb.st_mode&0100) ? 0 : 1); }