mycat/mycat.c

   1 /**************
   2 * Name:         mycat.c
   3 * Author:       Jan Vales (e0726236@student.tuwien.ac.at)
   4 * Date:         9.11.2009
   5 * Purpose:      reimplementation of "cat"
   6 * Usage:        Usage: cat [opt]
   7 * Output:       prints stdin to stdout
   8 * BspNr:        1h
   9 **************/
  10
  11 #include <stdio.h>
  12 #include <errno.h>
  13 #include <strings.h>
  14 #include <string.h>
  15 #include <assert.h>
  16 #include <stdlib.h>
  17 #include <getopt.h>
  18 #include <unistd.h>
  19
  20 /*Usage info, in case someone did something wrong*/
  21 void usage(char **argv){
  22         (void)fprintf(stderr,"%s Usage: mycat [opt]\n-E: replace newlines\n-T: replace Tabs\n-v: Print nonprintables (implies -E and -T)\n", argv[0]);
  23 }
  24
  25 /* main program. reads input from stdin and prints requested stuff to stdout*/
  26 int main(int argc, char **argv){
  27         int isOptE = 0;
  28         int isOptT = 0;
  29         int isOptv = 0;
  30         unsigned char c;
  31
  32         char temp;
  33         while((temp = getopt(argc, argv, "ETv")) != -1){
  34                 switch(temp){
  35                         case 'E': isOptE = 1; break;
  36                         case 'T': isOptT = 1; break;
  37                         case 'v': isOptv = 1; break;
  38                         default: usage(argv); return 1;
  39                 }
  40         }
  41
  42         for(;;){
  43                 c = getchar();
  44                 if(feof(stdin))break;
  45
  46                 if((isOptT | isOptv) & (c == '\t')){
  47                         (void)fprintf(stdout,"^I");
  48                         continue;
  49                 }
  50                 if((isOptE | isOptv) & (c == '\n')){
  51                         (void)fprintf(stdout,"$%c", c);
  52                         continue;
  53                 }
  54                 if(isOptv & (c >= 128)){
  55                         (void)fprintf(stdout,"M-");
  56                         c -= 128;
  57                 }
  58                 if(isOptv & (c == 127)){
  59                         (void)fprintf(stdout,"^?");
  60                         continue;
  61                 }
  62                 if(isOptv & (c <= 32)){
  63                         (void)fprintf(stdout,"^%c", (c+64));
  64                         continue;
  65                 }
  66                 (void)fprintf(stdout,"%c", c);
  67         }
  68         return 0;
  69 }
  70