posix_fallocate_sample.c

#include <stdio.h>
#include <fcntl.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>

int main(void)
{
        int fd, ret;
        char filename[] = "testfile";
        long size = 1024 * 1024 * 1024;

        fd = open(filename, O_RDWR|O_CREAT);

        if (fd==-1) {
                printf("open testfile is failed!:%s\n", strerror(errno));
                exit(1);
        }

        ret = posix_fallocate(fd, (off_t)0, (off_t)size);

        if (ret != 0) {
                printf("posix_fallocate is failed!:%s\n", strerror(ret));
                exit(1);
        }

        return 0;

}