gistfile1.txt

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[])
{

    FILE *f;
    FILE *frnd;
    int i = 0;

    if(argc != 4)
    {
        printf("Usage:\n\trnddata <file_name> <loop_count> <buffer_size>\n");
        return 1;
    }

    int BUFFER_SIZE = atoi(argv[2]);
    int BUFFER_COUNT = atoi(argv[3]); // get first commadn line arg as number

    unsigned char *buffer = (unsigned char*)malloc(BUFFER_SIZE);

    printf("Writing out %i payloads of %i Bytes each ...\n",BUFFER_COUNT,BUFFER_SIZE);

    // open our output file
    f = fopen(argv[1],"w");

    // open our random number source
    frnd = fopen("/dev/urandom","r");

    // create FILE_SIZE random bytes
    for(i = 0; i < BUFFER_COUNT; i++)
    {
        // read in BUFFER_SIZE random bytes
        fread(buffer,BUFFER_SIZE,1,frnd);

        // write out the buffer to our file
        fwrite(buffer,sizeof(buffer),1,f);

    }

    // close out our file (DON'T FORGET TO DO THIS)
    fclose(f);

    printf("Done.\n");

    // all done
    return 0;

}