/*****************************************************************************
*  FileIO.c
*  Illustrates file input-output commands and text processing using the
*  string functions strtok and strcat.
******************************************************************************/

#include<stdio.h>
#include<stdlib.h>
#include<string.h>

#define MAX_LEN 250


int main(int argc, char * argv[]){

   int n, count=0;
   FILE *in, *out;
   char line[MAX_LEN];
   char tokenlist[MAX_LEN];
   char* token;

   /* check command line for correct number of arguments */
   if( argc != 3 ){
      printf("Usage: %s infile outfile\n", argv[0]);
      exit(1);
   }

   /* open files for reading and writing */
   in = fopen(argv[1], "r");
   out = fopen(argv[2], "w");
   if( in==NULL ){
      printf("Unable to open file %s for reading\n", argv[1]);
      exit(1);
   }
   if( out==NULL ){
      printf("Unable to open file %s for writing\n", argv[2]);
      exit(1);
   }

   /* read each line of input file, then count and print tokens */
   while( fgets(line, MAX_LEN, in) != NULL)  {
      count++;
      n = 0;
      token = strtok(line, " \n");
      tokenlist[0] = '\0';
      while( token!=NULL ){
         strcat(tokenlist, "   ");
         strcat(tokenlist, token);
         strcat(tokenlist, "\n");
         n++;
         token = strtok(NULL, " \n");
      }
      fprintf(out, "line %d contains %d token%s: \n", count, n, n==1?"":"s");
      fprintf(out, "%s\n", tokenlist);
   }

   /* close files */
   fclose(in);
   fclose(out);

   return(0);
}