Hello!

For now to cut out the first empty element from @files i`ve just used shift(@files);

No, it's not a good idea, better make sure the path is valid before adding it, or at least before calling gbak.

Using a file search and backup what it finds is also not a good idea for production code, maybe only as an learning exercise, for the reason you gave yourself, it may skip some databases without even noticing. Better to make a config with all databases to backup, check everything that you think (or even what you don't thing :) ) that it can go wrong and log the errors.

use strict;
use warnings;

my @files;
my @ext = (qw{fb gdb ib fdb});

my $data = "/opt/databases/";                     # notice the final /

foreach my $ext (@ext) {
    my @load = glob "$data*.$ext";
    push (@files, @load);
}

foreach my $db (@files) {
    if (-f $db) {
        print "Found database: $db \n";
    }
    else {
        print "skiping '$db'...\n";
    }
}

# Alternatively:

foreach my $ext (@ext) {
    my @load = glob "$data*.$ext";
    foreach my $file (@load) {
        if (-f $file) {
            push (@files, $file);
        }
        else {
            print "Something is wrong, with '$file'!\n";
        }
    }
}

foreach my $db (@files) {
    print "Found database: $db \n";
}
[download]

Here is a piece from my backup script based on "IPC::Run3 - run a subprocess with input/ouput redirection", learned from Re^3: Using SYSTEM2 on Windows, thanks to ikegami :)

use strict;
use warnings;
use IPC::Run3 qw( run3 );

my $FBUSER = 'SYSDBA';
my $FBPASS = 'masterkey'; # this is secret ;)
my $gbak = 'gbak';
my $host = 'localhost';
my $db = '/opt/databases/test.fdb';
my $bk = '/opt/databases/backup/test.fbk';

# Backup the database on remote (or local) server
my $cmd = qq{$gbak -backup -service "$host:service_mgr" "$db" "$bk" -u
+ser "$FBUSER" -pass "$FBPASS"};

run3 $cmd, undef, \my @out, \my @err;

print "STDOUT: $_" for @out;
if (scalar @err > 0) {
    print "\n--- Errors ----------------------------------------------
+---\n";
    print " $_" for @err;
    print "-----------------------------------------------------------
+-\n\n";
}
else {
    print " Backup completed successfully.\n";
}
[download]

Regards, Ştefan

Update: refactored code that was silently skipping elements from the list.