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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include <netinet/in.h>
void usage()
{
fprintf(stderr, "Usage: generate_randfile [-s seed] [-f file] count\n");
exit(1);
}
int main(int argc, char **argv)
{
if(argc < 2)
{
usage();
}
unsigned int seed = getpid() ^ time(NULL);
FILE *fp = stdout;
int int_c;
while(-1 != (int_c = getopt(argc, argv, "s:f:")) )
{
switch(char(int_c))
{
case '?':
case ':':
usage();
break;
case 's':
if(sscanf(optarg, "%u", &seed) != 1)
usage();
break;
case 'f':
fp = fopen(optarg, "w");
if(fp == NULL)
usage();
break;
}
}
if(optind >= argc)
usage();
int count = atoi(argv[optind]);
srand(seed);
fprintf(stderr, "Generating %d random numbers with seed %d.\n", count, seed);
for(int i = 0; i < count; i++)
{
unsigned long val = htonl(rand());
if(fwrite(&val, sizeof(val), 1, fp) != 1)
{
fprintf(stderr, "Can't write item %d.\n", i);
return 1;
}
}
if(fp != stdout)
fclose(fp);
return 0;
}
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