Hi

I just stumbled across an (for me) very unexpected behaviour with open: 

use strict;
my $file;
open my $fh, "<", $file or die $!;
print "here\n";

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This prints "no such file or directory", as expected.

But 

use strict;
open my $fh, "<", $ARGV[0] or die $!;
print "here\n";

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This prints "here" - i.e. does not raise an exception when called without command-line arguments.

And finally 

use strict;
open my $fh, "<", undef or die $!;
print "here\n";

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Also does not raise an exception.

What is going on here?

I am using 5.26.1.

Many thanks!

In reply to open undef by morgon

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