2.9BSD/bin/istext.c

#include <sys/types.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>


int main(int argc, char *argv[])
{
  FILE *zin;
  int text,all;
  int i,ch,dodelete=0;
  float percent;
  extern int errno;


  if (argc<2) { printf("Usage: istext [-d] filename ...\n"); exit(1); }
  if (!strcmp(argv[1],"-d")) { dodelete=1; argc--; argv++; }

  for (i=1;i<argc;i++) {
    zin = fopen(argv[i], "r");
    if (zin == NULL) {
      printf("Could not open %s: %s\n", argv[i], strerror(errno)); continue;
    }
    all=0;text=0;
    while (!feof(zin)) {
      ch=fgetc(zin);
      if (ch==-1) break;
      all++;
      if (isprint(ch)) { text++; continue; }
      if ((ch=='\t') || (ch=='\r') || (ch=='\n') || (ch=='\b'))
			{ text++; continue; }
    }
    fclose(zin); if (all==0) all=1;
    percent= (float)text/(float)all;
    if (percent<0.9) {
      if (dodelete) unlink(argv[i]);
      else printf("remove %s: %3.3f\n",argv[i],100.0 * percent);
    }
  }
  exit(0);
}