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C/C++ Source or Header  |  1979-01-10  |  2.1 KB  |  163 lines
  1. #include <stdio.h>
  2. #include <ctype.h>
  3.  
  4. FILE *dfile;
  5. char *filenam  = "/usr/dict/words";
  6.  
  7. int fold;
  8. int dict;
  9. int tab;
  10. char entry[250];
  11. char word[250];
  12. char key[50];
  13.  
  14. main(argc,argv)
  15. char **argv;
  16. {
  17.     register c;
  18.     long top,bot,mid;
  19.     while(argc>=2 && *argv[1]=='-') {
  20.         for(;;) {
  21.             switch(*++argv[1]) {
  22.             case 'd':
  23.                 dict++;
  24.                 continue;
  25.             case 'f':
  26.                 fold++;
  27.                 continue;
  28.             case 't':
  29.                 tab = argv[1][1];
  30.                 if(tab)
  31.                     ++argv[1];
  32.                 continue;
  33.             case 0:
  34.                 break;
  35.             default:
  36.                 continue;
  37.             }
  38.             break;
  39.         }
  40.         argc --;
  41.         argv++;
  42.     }
  43.     if(argc<=1)
  44.         return;
  45.     if(argc==2) {
  46.         fold++;
  47.         dict++;
  48.     } else
  49.         filenam = argv[2];
  50.     dfile = fopen(filenam,"r");
  51.     if(dfile==NULL) {
  52.         fprintf(stderr,"look: can't open %s\n",filenam);
  53.         exit(2);
  54.     }
  55.     canon(argv[1],key);
  56.     bot = 0;
  57.     fseek(dfile,0L,2);
  58.     top = ftell(dfile);
  59.     for(;;) {
  60.         mid = (top+bot)/2;
  61.         fseek(dfile,mid,0);
  62.         do {
  63.             c = getc(dfile);
  64.             mid++;
  65.         } while(c!=EOF && c!='\n');
  66.         if(!getword(entry))
  67.             break;
  68.         canon(entry,word);
  69.         switch(compare(key,word)) {
  70.         case -2:
  71.         case -1:
  72.         case 0:
  73.             if(top<=mid)
  74.                 break;
  75.             top = mid;
  76.             continue;
  77.         case 1:
  78.         case 2:
  79.             bot = mid;
  80.             continue;
  81.         }
  82.         break;
  83.     }
  84.     fseek(dfile,bot,0);
  85.     while(ftell(dfile)<top) {
  86.         if(!getword(entry))
  87.             return;
  88.         canon(entry,word);
  89.         switch(compare(key,word)) {
  90.         case -2:
  91.             return;
  92.         case -1:
  93.         case 0:
  94.             puts(entry,stdout);
  95.             break;
  96.         case 1:
  97.         case 2:
  98.             continue;
  99.         }
  100.         break;
  101.     }
  102.     while(getword(entry)) {
  103.         canon(entry,word);
  104.         switch(compare(key,word)) {
  105.         case -1:
  106.         case 0:
  107.             puts(entry,stdout);
  108.             continue;
  109.         }
  110.         break;
  111.     }
  112. }
  113.  
  114. compare(s,t)
  115. register char *s,*t;
  116. {
  117.     for(;*s==*t;s++,t++)
  118.         if(*s==0)
  119.             return(0);
  120.     return(*s==0? -1:
  121.         *t==0? 1:
  122.         *s<*t? -2:
  123.         2);
  124. }
  125.  
  126. getword(w)
  127. char *w;
  128. {
  129.     register c;
  130.     for(;;) {
  131.         c = getc(dfile);
  132.         if(c==EOF)
  133.             return(0);
  134.         if(c=='\n')
  135.             break;
  136.         *w++ = c;
  137.     }
  138.     *w = 0;
  139.     return(1);
  140. }
  141.  
  142. canon(old,new)
  143. char *old,*new;
  144. {
  145.     register c;
  146.     for(;;) {
  147.         *new = c = *old++;
  148.         if(c==0||c==tab) {
  149.             *new = 0;
  150.             break;
  151.         }
  152.         if(dict) {
  153.             if(!isalnum(c))
  154.                 continue;
  155.         }
  156.         if(fold) {
  157.             if(isupper(c))
  158.                 *new += 'a' - 'A';
  159.         }
  160.         new++;
  161.     }
  162. }
  163.