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
|