perl function endhostent

The endhostent function in Perl is used to free system resources associated with the host file that were previously allocated by the gethostent function. Here's an example of how to use endhostent:

use Socket;
use POSIX qw(gethostent endhostent);

my $hostname = 'localhost';
my $ip;

while (my ($name, $aliases, $addrtype, $length, @addrs) = gethostent()) {
  if ($name eq $hostname) {
    $ip = inet_ntoa($addrs[0]);
    last;
  }
}

endhostent();

print "IP address for $hostname: $ip\n";

In this example, the gethostent function is used in a loop to iterate over each entry in the system's host file. For each host entry, the script checks if its name matches the value of $hostname. If a matching host is found, its first IP address is converted to a string using the inet_ntoa function and stored in the $ip variable. The loop is then exited using the last keyword.

After the loop has finished, the endhostent function is called to free system resources associated with the host file. Finally, the script prints the IP address corresponding to the hostname specified by $hostname.

The endhostent function is typically used after calling gethostent, gethostbyaddr, or gethostbyname to ensure that system resources are properly freed. If you forget to call endhostent, it may cause resource leaks or other issues.