#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <sys/mman.h>
#include <unistd.h>

void
usage(void)
{
	fprintf(stderr, "bigmem <anon size(MB)>\n");
}

int
main(int argc, char *argv[])
{
	void *buf;
	size_t size;
	pid_t pid;

	if (argc != 2) {
		usage();
		return 1;
	}

	pid = getpid();
	fprintf(stdout, "pid is %d\n", pid);

	size = atol(argv[1]) * 1024 * 1024;
	buf = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
	if (buf == MAP_FAILED) {
		perror(NULL);
		return errno;
	}

	memset(buf, 0, size);
	fprintf(stdout, "allocated %ld bytes anonymous memory\n");

	pause();
}