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how to dynamically create multiple files

how to dynamically create multiple files

how to dynamically create multiple files


I need help on creating create multiple files dynamically, meaning, creating a file when i need to write in it, then move to another file to write some other things...

because FILE *'s need to be declared ahead of time... i don't know how to create this recursively... I don't know how many files i need to create until run time.

Thank you for any suggestion!

RE: how to dynamically create multiple files

Simple way:
Create static array with ptr to FILE arguments, and realloc this array when you need. And init two static integers, one to control array size, other - for current file in use.

RE: how to dynamically create multiple files

How exactly is it that you determine the file names during run time? Read them from a file? Get them from a user? What?

You can reuse a FILE variable. Below is some basic code for getting the file names from a user.

/**** Untested ****/

#include <stdio.h>
#include <string.h>

int main(void)
    FILE *fp;
    char fname[FILENAME_MAX+1];

    printf("Enter file names, CTRL-D to quit\n");

    while (NULL!=fgets(fname,sizeof buf,stdin)) {
        if (NULL!=strrchr(fname,'\n')) {
        if (NULL==(fp=fopen(fname,"w")) {
            fprintf(stderr,"Failed to open %s\n",fname);
        /* Do some stuff with the file */
    return 0;

Is this similar to what you want to do or did I misunderstand the intent of your question?



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