Question

I have a little problem. I need to do some little operations on quite many files in one little program. So far I have decided to operate them in a single loop where I just change the number after the name. The files are all named TFxx.txt where xx is increasing number from 1 to 80. So how can I open them all in a single loop one after one? I have tried this:

for(i=1; i<=80; i++) {
   char name[8] = "TF"+i+".txt";
   FILE = open(name, r);
   /* Do something */
  }

As you can see the second line would be working in python but not in C. I have tried to do similiar running numbering with C to this program, but I haven’t found out yet how to do that. The format doesn’t need to be as it is on the second line, but I’d like to have some advice of how can I solve this problem. All I need to do is just be able to open many files and do same operations to them.

Answer 1

You can use sprintf as follows:

for(i=0; i<=80; i++) {
   char name[32];
   memset(name, 0, sizeof(name));
   FILE *fp;
   sprintf(name, "TF%d.txt", i);
   fp = fopen(name, "r");
   /* Do something */
  }