1#define _GNU_SOURCE
2#include <errno.h>
3#include <string.h>
4#include <sys/utsname.h>
5#include <unistd.h>
6
7int getdomainname(char* name, size_t len) {
8    struct utsname temp;
9    uname(&temp);
10    if (!len || strlen(temp.domainname) >= len) {
11        errno = EINVAL;
12        return -1;
13    }
14    strcpy(name, temp.domainname);
15    return 0;
16}
17