#include <fcntl.h>
#include <stdio.h>

void main(int argc, char *argv[]) {
  FILE *f, *g;
  char buf[8192], *q;
  int a, b, len;

  memset(buf, 0, 8192);

  if(argc < 2) {
    fprintf(stderr, "Usage: %s [pattern] [file...]\n", argv[0]);
    exit(1);
  }

  for(a=1;a<argc;a++) {
    if(!(f=fopen(argv[a], "r"))) {
      perror(argv[a]);
      continue;
    }

    if((q=strrchr(argv[a], '/')))
      strcpy(buf, q+1);
    else {
      strcpy(buf, argv[a]);
      strcat(buf, "~");
    }

    g=fopen(buf, "w");
    while((len=fread(buf, 1, 4096, f))) {
      for(b=0;b<len;b++)
        buf[b]+=32;
      for(b=0;b<len;b++)
        if(buf[b] < 32)
          buf[b]=' ';
      fwrite(buf, len, 1, g);
    }

    fclose(f);
  }
}