Parsing specific data from one text file to another..

Hello all,

Thank you in advance for any help you can provide. This is my second plee for help I haven't programmed in years, but was asked by my boss to come up with a simple program to parse some information. Basically, we will pass through the command line: Program [infile] [outfile].

The infile looks similar to this:

Code:

info 
info
info
info

START
123456       garbage
654321       garbage
Hello        garbage
Goodbye      garbage

All the "info" can be ignored. As has to be the "garbage". The info that has to be collected always begins below the "START" statement. I'm looking to collect all data below the "START" that begins in the 0 column. Anything else on an individual line should be ignored except the first string. What the result file should look like is simply:

Code:

123456
654321
Hello
Goodbye

I have no problem opening and writing to a file (I don't believe) but was looking for some pointers as to how to pull the first column string and only that, once past the START marker.


Thanks again.

Maybe something like this.

Code:

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

int main()
{
   static const char filename[] = "file.txt";
   FILE *file = fopen(filename, "r");
   if ( file != NULL )
   {
      char text[12];
      int ready = 0;
      while ( fscanf(file, "%11s%*[^\n]%*c", text) == 1 )
      {
         if ( ready )
         {
            puts(text);
         }
         else if ( strcmp(text, "START") == 0 )
         {
            ready = 1;
         }

      }
   }
   else
   {
      perror(filename);
   }
   return 0;
}

/* file.txt
info
info
info
info

START
123456       garbage
654321       garbage
Hello        garbage
Goodbye      garbage
*/

/* my output
123456
654321
Hello
Goodbye
*/

Thanks a million Dave. I will work on the in/outfile portion. I'll let you know if i hit a snag. Thanks again.