Question

In C, I want to create and open text files to write data into, but the problem is I want to name the files on the go, such as

FILE *ptr;

for(i=0;i<1000;i++){
   fopen_s(&ptr,"i.txt","w");
   operations to fill data into file i.txt;
   fclose(ptr);
}

such that I will create file 0.txt, 1.txt, 2.txt … 999.txt.

How is this possible? I checked open and rename functions, but couldn’t find a way to do.

Thank you so much for all your help.
Best,

Answer 1

use snprintf to set the file number:

FILE *ptr;
char name[FILENAME_MAX];

for(i=0;i<1000;i++){
   snprintf(name, sizeof(name), "%d.txt", i);
   fopen_s(&ptr, name, "w");
   //operations to fill data into file i.txt;
   fclose(ptr);
}