4.3BSD - /usr/src/ucb/fold.c

   1: /*
   2:  * Copyright (c) 1980 Regents of the University of California.
   3:  * All rights reserved.  The Berkeley software License Agreement
   4:  * specifies the terms and conditions for redistribution.
   5:  */
   6: 
   7: #ifndef lint
   8: char copyright[] =
   9: "@(#) Copyright (c) 1980 Regents of the University of California.\n\
  10:  All rights reserved.\n";
  11: #endif not lint
  12: 
  13: #ifndef lint
  14: static char sccsid[] = "@(#)fold.c	5.1 (Berkeley) 5/31/85";
  15: #endif not lint
  16: 
  17: #include <stdio.h>
  18: /*
  19:  * fold - fold long lines for finite output devices
  20:  *
  21:  * Bill Joy UCB June 28, 1977
  22:  */
  23: 
  24: int fold =  80;
  25: 
  26: main(argc, argv)
  27:     int argc;
  28:     char *argv[];
  29: {
  30:     register c;
  31:     FILE *f;
  32: 
  33:     argc--, argv++;
  34:     if (argc > 0 && argv[0][0] == '-') {
  35:         fold = 0;
  36:         argv[0]++;
  37:         while (*argv[0] >= '0' && *argv[0] <= '9')
  38:             fold *= 10, fold += *argv[0]++ - '0';
  39:         if (*argv[0]) {
  40:             printf("Bad number for fold\n");
  41:             exit(1);
  42:         }
  43:         argc--, argv++;
  44:     }
  45:     do {
  46:         if (argc > 0) {
  47:             if (freopen(argv[0], "r", stdin) == NULL) {
  48:                 perror(argv[0]);
  49:                 exit(1);
  50:             }
  51:             argc--, argv++;
  52:         }
  53:         for (;;) {
  54:             c = getc(stdin);
  55:             if (c == -1)
  56:                 break;
  57:             putch(c);
  58:         }
  59:     } while (argc > 0);
  60:     exit(0);
  61: }
  62: 
  63: int col;
  64: 
  65: putch(c)
  66:     register c;
  67: {
  68:     register ncol;
  69: 
  70:     switch (c) {
  71:         case '\n':
  72:             ncol = 0;
  73:             break;
  74:         case '\t':
  75:             ncol = (col + 8) &~ 7;
  76:             break;
  77:         case '\b':
  78:             ncol = col ? col - 1 : 0;
  79:             break;
  80:         case '\r':
  81:             ncol = 0;
  82:             break;
  83:         default:
  84:             ncol = col + 1;
  85:     }
  86:     if (ncol > fold)
  87:         putchar('\n'), col = 0;
  88:     putchar(c);
  89:     switch (c) {
  90:         case '\n':
  91:             col = 0;
  92:             break;
  93:         case '\t':
  94:             col += 8;
  95:             col &= ~7;
  96:             break;
  97:         case '\b':
  98:             if (col)
  99:                 col--;
 100:             break;
 101:         case '\r':
 102:             col = 0;
 103:             break;
 104:         default:
 105:             col++;
 106:             break;
 107:     }
 108: }

Defined functions

Defined variables