/* about.c * * Usage: about [] * * Examples: about calloc * about * * about * b:c.cat * about fourier b:math.dat * * Description: For each line in beginning as ":", * successive lines are displayed until the next line * begins with ":"; if is *, all entries are * displayed; defaults to "about.dat". * * Purpose: The file about.dat contains synopses of C functions, * thus making "about" an elementary "help facility". * * However, may be any list of :'s of * interest, with each name on a separate line, and * each followed by its respective text to be displayed. * * Limitations: A simple linear search is used, so probably no more * than a few hundred names can be handled usefully. * * Language: C (DeSmet 2.4) * * Author: R. E. Sawyer * 3620 Spencer St. 30, Torrance, CA 90503 * 1 Jan 85 */ #define CATFILE "about.dat" #define DEFCHAR ':' #define BUFLEN 82 int fin; main(ac, av) int ac; char *av[]; { char *catfile; char buf[BUFLEN]; int showall; int done; int more; showall = 0; done = 0; if ((ac < 2) || (ac > 3)) { printf("\nUsage: about []\n"); printf("\nFor each line in beginning as \":\","); printf("\nsuccessive lines are displayed until the next line"); printf("\nbegins with \":\"; if is *, all entries are"); printf("\ndisplayed; defaults to \"about.dat\".\n"); exit(); } else if (ac == 2) { if ((fin = fopen(catfile = CATFILE, "r")) == 0) { printf("\n---File %s not found", catfile); exit(); } } else if (ac ==3) { if ((fin = fopen(catfile = av[2], "r")) == 0) { printf("\n---File %s not found", catfile); exit(); } } if (*av[1] == '*') showall = 1; printf("\n(Catalogue file: %s)\n\n", catfile); more = fgets(buf, BUFLEN - 1, fin); while (more) { if ((buf[0] == DEFCHAR) && ((comp(av[1], buf + 1) == 0) || showall)) { more = print_text(buf); if (!showall) { done = 1; break; } } else more = fgets(buf, BUFLEN - 1, fin); } if ((done != 1) && !showall) printf("\"%s\" is not catalogued\n\n", av[1]); fclose(fin); } int comp(s, t) char *s, *t; { int i; for (i = 0; (t[i] > ' ') && (t[i] <= '~'); ++i) ; t[i] = '\0'; return strcmp(s, t); } int print_text(buf) char buf[]; { int more; printf("%s:\n", &buf[1]); while (((more = fgets(buf, BUFLEN - 1, fin)) != 0) && (buf[0] != DEFCHAR)) { puts(buf); } return more; }