Reading text file-writting binary file

Hi guys. I just need some advice here.
I have a text file ( containg strings and numbers)
I read the file ("r") and every string and number should be saved in a binary file. After that I would like to read back the binary file and save it all in another text file.
I'm working in C.
What I did so far is get the strings and numbers (one by one) and use - for strings - fwrite(string,sizeof(char)*strlen(str),output_file). The string is stored ok (I don't know if this is in binary state or not, but after the string, it adds weird data and the numbers are not stored ok. Any help would apreciated. Thanks

Use a struct for storing your strings as char[] and numbers as int. Write out the structs to a binary file like this:

#include <stdio.h>

struct binstr
{
   char bigStr[100];
};

void main()
{
   FILE *f;
   struct binstr BS;
   struct binstr GS;

   f = fopen("binfile", "w" );

   strcpy( BS.bigStr,  "Hello There" );

   fwrite( &BS, sizeof(struct binstr), 1, f );

   fclose( f );

   f = fopen("binfile", "r" );
   fread( &GS, sizeof( struct binstr ), 1, f );
   printf("Str is: %s\n", GS.bigStr );

   fclose( f );

}

Thanks crabboy, I managed to write it myself.

Ok, I managed to fvck this up. The struct contains some integers and few strings of unknow size. Is there an easy way to to write this struct to the binary file?
Thanks

The strings need to be a fixed size.

this might be helpful
this is basically the same as cat-ing everything under ascii 127:

#include "stdio.h"

main(int argc, char *argv[])
{
 int c;
 FILE * fstream;

 fstream = fopen(argv[1], "r");
 c = fgetc(fstream);

 while(c != EOF)
 {
  if(c >= 0 && c <= 127)
   printf("%c", c);
  c = fgetc(fstream);
 }
 fclose(fstream);
}

feel free to modify to your heart's content