Re: Is this the most elegant way to code directory lookup?

With your helpful suggestions I have modified my code as follows. Better? I hope so. =]

#!/usr/bin/perl
use warnings;
use strict;

use File::Copy;

# change source backup dir, modification time, and destination backup 
+dir here
my $srcdir = '/var/local/somedir';
my $mtime = '1';
my $destdir = '/backup/somedir';

die "Error:$!" unless (-d $srcdir && -d $destdir );

print "Beginning backup...\n";

chdir $srcdir;
opendir(INDIR,$srcdir) || die "Can't open directory: $!";

while ($_ = readdir(INDIR)) {

        next if (-d || $_ eq "." || $_ eq "..");

        if (-M > $mtime) {
                print "$_ : Older than one day.\n";
        } else {
                system("tar -cz $_ -f $_.tar.gz");
                move(<*.gz>, $destdir) && print "$_ archived in $destd
+ir\n";
        }

}
closedir(INDIR);
print "Backup complete.\n";
[download]

Comment on Re: Is this the most elegant way to code directory lookup? Download Code

Replies are listed 'Best First'.
Re^2: Is this the most elegant way to code directory lookup? by davorg (Chancellor) on Sep 29, 2006 at 15:20 UTC
die "Error:$!" unless (-d $srcdir && -d $destdir ); As I mentioned before, $! won't have anything useful in it at this point, so there's no reason to include it in the error message. Why not make the error messages a little clearer. `die "$srcdir is not a valid directory\n" unless -d $srcdir; die "$destdir is not a valid directory\n" unless -d $destdir;` [download] Update: Looks like I'm wrong. -- <http://dave.org.uk> "The first rule of Perl club is you do not talk about Perl club." -- Chip Salzenberg	[reply] [d/l]
Re^3: Is this the most elegant way to code directory lookup? by hv (Prior) on Oct 02, 2006 at 10:18 UTC
Update: Looks like I'm wrong. I disagree: just because someone tried it once and got a useful error message doesn't change the fact that `$!` is not documented to be defined at this point. `$!` may well get set differently (or not at all) in different circumstances, when testing different files, or on a different O/S, or depending on phase of the moon for all we know. Your suggested clearer error messages are definitively more correct; the only change I might make (at the risk of getting too clever) is to avoid the duplication with something like: `die "$_ is not a valid directory\n" for grep !-d, $srcdir, $destdir;` [download] Hugo	[reply] [d/l] [select]


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