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Fellow Monks,
I must confess I am confused.

In one of my programs I concatenate some user-provided strings to build a file-match pattern which I then feed to bsd_glob from the File::Glob module. Then I need to detect whether it matched some files and proceed doing something with them. Sounds quite straightforward to me. But during this I ran into a strange runtime behaviour that I could boil down to the following test script:

#! /usr/bin/perl use strict; use warnings; use Data::Dumper; use File::Glob qw/:glob/; # There lives a file "passwords.dat" in the current directory.... # This matches the whole filename. OK my $pat1 = "passwords.dat"; print "\nPATT $pat1\n"; print "PRE ERR: ", Dumper($!); my @list = bsd_glob($pat1, GLOB_ERR); print Dumper(\@list); print "POST ERR: ", Dumper($!); print "\n"; # This file is not there so it doesn't match and afterwards $! ist # set. OK my $pat2 = "this_will_miss_in_globbing"; print "\nPATT $pat2\n"; print "PRE ERR: ", Dumper($!); @list = bsd_glob($pat2, GLOB_ERR); print Dumper(\@list); print "POST ERR: ", Dumper($!); print "\n"; # This should match again since it is just the same as the first match # but *afterwards $! ist still set*!!?? my $pat3 = "passwords.dat"; print "\nPATT $pat3\n"; print "PRE ERR: ", Dumper($!); @list = bsd_glob($pat3, GLOB_ERR); print Dumper(\@list); print "POST ERR: ", Dumper($!); print "\n"; # This resets $! back to normal which is just fine my $pat4 = "*.dat"; print "\nPATT $pat4\n"; print "PRE ERR: ", Dumper($!); @list = bsd_glob($pat4, GLOB_ERR); print Dumper(\@list); print "POST ERR: ", Dumper($!); print "\n";
Using GLOB_ERR or GLOB_NOCHECK or both of them changes nothing. Now my questions are
  • Why is the variable $! not reset back to normal on successful glob with $pat3?
  • How do I get bsd_glob() to do just that?
  • What is The Right Way to check the outcome of bsd_glob?
I assume that the error is on my side since this module is a core module which is even used to implement Perls glob() built-in.

Regards... stefan k
you begin bashing the string with a +42 regexp of confusion


In reply to bsd_glob does not reset $! by stefan k

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