#!/usr/bin/env perl

use strict;
use warnings;
use Fcntl qw[];

for my $file ('/tmp/testlink', '/etc/passwd', '/etc') {
print "--- $file is link: ", -l $file, "\n";
my $mode = (stat($file))[2];
my $lmode = (lstat($file))[2];
printf "mode:     %016b\n", $mode;
printf "lmode:    %016b\n", $lmode;
printf "S_IFMT(): %016b\n", Fcntl::S_IFMT($lmode);
printf "S_IFMT:   %016b\n", Fcntl::S_IFMT() & $lmode;
printf "S_IFMT:   %016b\n", Fcntl::S_IFMT();
printf "S_IFLNK:  %016b\n", Fcntl::S_IFLNK();
printf "S_IFLNK:  %016b\n", (Fcntl::S_IFLNK() & Fcntl::S_IFMT() & $lmode) == Fcntl::S_IFLNK() ;
printf "S_ISLNK():%016b\n", Fcntl::S_ISLNK($lmode);
print "---\n";
}

__END__
--- /tmp/testlink is link: 1
mode:     0100001111111111
lmode:    1010000111111111
S_IFMT(): 1010000000000000
S_IFMT:   1010000000000000
S_IFMT:   1111000000000000
S_IFLNK:  1010000000000000
S_IFLNK:  0000000000000001
S_ISLNK():0000000000000001
---
--- /etc/passwd is link:
mode:     1000000110100100
lmode:    1000000110100100
S_IFMT(): 1000000000000000
S_IFMT:   1000000000000000
S_IFMT:   1111000000000000
S_IFLNK:  1010000000000000
S_IFLNK:  0000000000000000
S_ISLNK():0000000000000000
---
--- /etc is link:
mode:     0100000111101101
lmode:    0100000111101101
S_IFMT(): 0100000000000000
S_IFMT:   0100000000000000
S_IFMT:   1111000000000000
S_IFLNK:  1010000000000000
S_IFLNK:  0000000000000000
S_ISLNK():0000000000000000
---