fabrizio_start_perl has asked for the wisdom of the Perl Monks concerning the following question:

Hi Support, I have created a perl script that read a configuration file and extract from it one field if pattern match (field separator is ;;) If i run it on Linux host it works corretcly but if i try to run the script on Windows one it fails (it does not print $1 value) The perl version is for both environment v5.8.8. This an example of entry in configuration file: 
hostname1;;/tmp/fab/app01/log/app01.log /tmp/fab/app01/log/app02.stder
+r /tmp/fab/app01/log/app03.stdout;;
hostname2;;C:\temp\log\loga.txt C:\temp\log\logb.txt;;

[download]

#!/opt/OV/contrib/perl/bin/perl

#Set my variables

my $in_file = $ARGV[0];

#my $in_file = 'configuration_logfile_weblogic';
open my $in_fh, '<', $in_file or die "Could not open file $in_file: $!
+";

my $fqdn = `hostname`;

@hostname_short = split(/\./,$fqdn,2);

my $hostname = "@hostname_short[0]";

$hostname=~ tr/A-Z/a-z/;

while ( my $line = <$in_fh> ) {
        if($line =~ m/^$hostname;;(.*);;/) {
        print $1;
        }
}

close $in_fh  or die "Could not close file $in_file: $!";

[download]
Can you help me ? Thanks. Fabrizio

Replies are listed 'Best First'.
Re: Perl - pattern matching
by hazylife (Monk) on Mar 31, 2014 at 11:36 UTC
    if i try to run the script on Windows one it fails
    And the fqdn of that Windows host is just one single word, right? Try chomping it like this: 
    chomp(my $fqdn = `hostname`);

# OR, much better:
my ($hostname) = `hostname` =~ /([-a-zA-Z0-9]+)/;
$hostname=~ tr/A-Z/a-z/;

    [download]
    update: no, ([^.]+) won't do
[reply]
[d/l]
[select]

      Hi,

      may I suggest to use the following CORE module (even no addon installation necessary):

      use Sys::Hostname;
my $hostname = hostname;

      [download]

      No subprocess is spawned and hopefully all OS dependent aspects considered. IMHO a much better approach.

      best regards
      McA

[reply]
[d/l]
      Great now it works ! Thanks a lot ! Fabrizio
[reply]
Re: Perl - pattern matching
by kcott (Archbishop) on Mar 31, 2014 at 14:01 UTC

    G'day Fabrizio,

    Welcome to the monastery.

    Here's a couple of points unrelated to your "pattern matching" query.

    I see you've attempted to use lexical variables (with my) throughout your code — which is good. Had you used this line at the top of your code: 

    use strict;

    [download]

    The 'vars' stricture of strict would have alerted you to the fact that you'd forgotten to do this for @hostname_short.

    Had you also used this line at the top of your code: 

    use warnings;

    [download]

    The 'syntax' category of warnings would have emitted a message that actually gave you a better way to write @hostname_short[0]: 

    Scalar value @hostname_short[0] better written as $hostname_short[0]

    [download]

    Using both of these pragmata in all of your scripts is a very good idea.

    As it turns out, you could have written both of these lines: 

    @hostname_short = split(/\./,$fqdn,2);

my $hostname = "@hostname_short[0]";

    [download]

    as just this single line:

    my $hostname = (split /\./, $fqdn, 2)[0];

    [download]

    -- Ken

[reply]
[d/l]
[select]
      Thanks!
[reply]
        Hi, I continue working on my script and now is more powerfull :) ! I have a question about this section 
                chomp (my $OVINSTDIR = `echo %OvInstallDir%`);
                        if(-e $OVINSTDIR.'\bin\win64\opcmon.exe'){
                        my $COMMAND = $OVINSTDIR.'\bin\win64\opcmon.ex
+e';
                        $OPCMON="$COMMAND";
                        qx[$OPCMON];
                        }

        [download]
        when i execute the command $OVINSTDIR.'\bin\win64\opcmon.exe' i got error: 'C:\Program' is not recognized as an internal or external command, because variable $OVINSTDIR contains space (C:\Program Files\HP\HP BTO Software\) How can i manage this behavior ? Thanks, Fabrizio
[reply]
[d/l]

Back to Seekers of Perl Wisdom