Thread: Scanning of filename_i.dat files with i=1:N in a C code.

Next time, please post your code between code tags.
Fuzzy pictures are useless for copy/pasting your work into a fixed up example.

So, briefly

Code:

#define N 100
int main ( ) {
  struct something Re[N+1] = { 0 };  // your struct, initialised
  for ( int i = 1 ; i <= N ; i++ ) {
    char filename[100];
    sprintf(filename,"S809_%d.dat",i);
    FILE *fp = fopen(filename,"r");
    // your while loop, adjusting Re1 to Re[i]
    fclose(fp);
  }
}

But watch out if your N * sizeof(struct something) is very large (like more than 1MB).

If N isn't a compile time constant, say so.