Quickly create large file on a Windows system

Question

In the same vein as Quickly create a large file on a Linux system, I\'d like to quickly create a large file on a Windows system. By large I\'m thinking 5 GB.

Answer 1

Plain ol' C... this builds under MinGW GCC on Windows XX and should work on any 'generic' C platform.

It generates a null file of a specified size. The resultant file is NOT just a directory space-occupier entry, and in fact occupies the specified number of bytes. This is fast because no actual writes occur except for the byte written before close.

My instance produces a file full of zeros - this could vary by platform; this program essentially sets up the directory structure for whatever data is hanging around.

#include 
#include 

FILE *file;

int main(int argc, char **argv)
{
    unsigned long  size;

    if(argc!=3)
    {
        printf("Error ... syntax: Fillerfile  size  Fname \n\n");
        exit(1);
    }

    size = atoi(&*argv[1]);

    printf("Creating %d byte file '%s'...\n", size, &*argv[2]);

    if(!(file = fopen(&*argv[2], "w+")))
    {
        printf("Error opening file %s!\n\n", &*argv[2]);
        exit(1);
    }

    fseek(file, size-1, SEEK_SET);
    fprintf(file, "%c", 0x00);
    fclose(file);
}