`gethostbyname()` fails

Hi!

I'm trying to run this simple socket example in sandbox2:
```
#include
#include
#include
#include
#include

#include
#include /* getprotobyname */
#include
#include
#include

extern int h_errno;

int main(int argc, char **argv) {
char *server_hostname = "localhost";
unsigned short server_port = 443;
char buffer[BUFSIZ];
char *user_input = "";
in_addr_t in_addr;
in_addr_t server_addr;
int sockfd;
ssize_t nbytes_read, i, user_input_len = 1;
struct hostent *hostent;
/* This is the struct used by INet addresses. */
struct sockaddr_in sockaddr_in;

if (argc > 1) {
server_hostname = argv[1];
if (argc > 2) {
server_port = strtol(argv[2], NULL, 10);
}
}

sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd == -1) {
perror("socket");
exit(EXIT_FAILURE);
}

/* Prepare sockaddr_in. */
hostent = gethostbyname(server_hostname); // <-------------- fails here
if (hostent == NULL) {
fprintf(stderr, "error: gethostbyname(\"%s\")\n", server_hostname);
printf("h_errno: %d\n", h_errno);
exit(EXIT_FAILURE);
}
in_addr = inet_addr(inet_ntoa(*(struct in_addr*)*(hostent->h_addr_list)));
if (in_addr == (in_addr_t)-1) {
fprintf(stderr, "error: inet_addr(\"%s\")\n", *(hostent->h_addr_list));
exit(EXIT_FAILURE);
}

sockaddr_in.sin_addr.s_addr = in_addr;
sockaddr_in.sin_family = AF_INET;
sockaddr_in.sin_port = htons(server_port);

/* Do the actual connection. */
if (connect(sockfd, (struct sockaddr*)&sockaddr_in, sizeof(sockaddr_in)) == -1) {
perror("connect");
return EXIT_FAILURE;
}
if (write(sockfd, user_input, user_input_len) == -1) {
perror("write");
exit(EXIT_FAILURE);
}
while ((nbytes_read = read(sockfd, buffer, BUFSIZ)) > 0) {
write(STDOUT_FILENO, buffer, nbytes_read);
}

exit(EXIT_SUCCESS);
}

```

Command:
`sandbox2tool --sandbox2tool_keep_env --sandbox2tool_mount_tmp --sandbox2tool_resolve_and_add_libraries --sandbox2tool_need_networking a.out`
Additionally the sandbox is configured to allow all syscalls (`DangerDefaultAllowAll()`).

I was expecting `gethostbyname()` to succeed and return a hostent struct containing one or several IP addresses.
Instead `gethostbyname()` fails with `h_errno=3 (NO_RECOVERY)`.
Interestingly passing an IP address directly to `gethostbyname()` instead of `localhost` doesn't fail.

What am I missing?
Cheers