Either use: 
use strict; 
use warnings;
use Fcntl qw(F_GETFL F_SETFL O_NONBLOCK);

my $file_name='/tmp/test_me.txt';

open my $fh,'>',$file_name || die "can't open $file_name for writing: 
+$!\n";
my $flags=fcntl $fh,F_GETFL,O_NONBLOCK || die "fcntl call failed: $!\n
+";
print "Flags: $flags\n";
close $fh || die "can't close write handle to $file_name: $!\n";

[download]
or capture your packed data into a variable: 
my $flags=fcntl(FH,F_GETFL,$_) || die "fcntl call failed: $!\n";

[download]

In reply to Re: Using fcntl function for the first time by Anonymous Monk
in thread Using fcntl function for the first time by matrixx515

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