The idiom I've normally used is more along the lines of something like this; call open then use constants from Errno to figure out from !$ what specifically went wrong and give more detailed advice. You can also use a variation on this to (e.g.) try and open a file for reading and fall back to another default location if !$ == ENOENT because it didn't exist; (EDIT) or you don't care if it didn't exist, but other errors you do want to bring to the user's attention. 

use Errno qw( :POSIX );
use Log::Log4perl;

## ...
if( open( my $fh, q{<}, $filename ) ) {
  my $frobulated_data = {};

  ## process with $fh

  close( $fh );
  return $frobulated_data;
} else {
  if( $! == ENOENT ) {
    ERROR( qq{Couldn't find file '$filename': $!} );
  } elsif( $! == EACCES ) {
    ERROR( qq{Problems with permissions for '$filename': $!} );
  } elsif( ## whatever else specific you want to handle ... ) { #...
  } else {
    ERROR( qq{Problem opening '$filename': $!} );
  }
  return;
}

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The cake is a lie.
The cake is a lie.
The cake is a lie.

In reply to Re^3: Testing unexpected I/O failures by Fletch
in thread Testing unexpected I/O failures by kcott

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