Hi All,

I am a newbie in C programming. I was facing a problem with reading a text file and writing it as it is but i need to round some of the floating numbers to six decimal digits. I am posting my code as it is and example of how my text file looks like. As I am a beginner I need some suggestions and guide me into the right direction.
Code:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>

/* data analysis for TI to sort out data by Integers, Floating Points,
   Binary numbers, strings, fields */

main()
{
    char ch, frst_100l[1024]; /* pointer ch character for file*/
    FILE *fp;  /* file pointer*/

  printf("frst_100l"); /* name of the file */
  gets(file_name);
 
   
  fp = fopen("frst_100l","r+");                                                                                                        ");/*open the file name*/



/*  if file is error , then excute error and exit failure */
  if(fp == NULL)
   {
     printf("\n Error while openeing the file:frst_100l
");
        exit (EXIT_FAILURE);
   } 



  
while( (Ch=getchar(fp))!=EOF) /* pointer ch to read the files 
{
 
    fputc(ch,fp);
    
    if ( fp == '.')
    {
       fputc(ch,fp)   if(fp==','of
       fputc(ch,fp)
       fputc(ch,fp)
       fputc(ch,fp)
       fputc(ch,fp)
       fputc(ch,fp)
    }
    if( fp == ',')
    {
      fputc(ch,fp);
    }
fclose(fp)
Example one line of the text file is below

04,-150,-75,-37,-18,-8,-4,6,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ,,,,,,,660.344421386719,,334.063598632813,
I also heard about atof function can anyone explain or educate me how that works....
Thanks,
Adoosa.