jamen_98 has asked for the wisdom of the Perl Monks concerning the following question:

I have an ASCII file about backup tapes like: 

Label         Location                  Start Time  End Time
NKL0289       MSL6000 Trinity: 7        18:45       20:45

[download]

What I'm looking to do is extract the 7 number which is the slot number the tape is in. I have tried several things like using substr() and grep, but I'm not so good at Perl and am struggling. I have done some perl before (long time ago) so I understand some things, but need a little help. I have tried several variations to this, but here it is: 
$slotnumber=0;
$dpdrivloc = "Trinity";

open(DPSLOTFILE, "< c:\\test.txt") or die "Can't open test.txt: $!";

while (<DPSLOTFILE>) {
    chomp;
    for $chunk (split) {
        print "$chunk\n";
    if ($chunk eq $dpdrivloc) {
        print "We have a match folks!";
    }
    }
}

    #system("c:\\ipbat.bat");

close DPSLOTFILE;

[download]
It also runs a batch file which I've commented out, but that works great already. I need to extract the number after MSL6000 Trinity: and place it after the the batch file with that number as an argument. I think I can handle that part though.

Edit by BazB remove pre tags.

Replies are listed 'Best First'.
Re: Extract field after keyword
by dragonchild (Archbishop) on Mar 19, 2004 at 19:32 UTC 
    while (<DPSLOTFILE>) {
    my ($slot) = /$dpdrivloc:\s*(\d+)/;
# Do something with $slot
}

    [download]

    ------
    We are the carpenters and bricklayers of the Information Age.

    Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

[reply]
[d/l]
      Tried:


      while (<DPSLOTFILE>) {
    my ($slot) = /$dpdrivloc:\s*(\d+)/;
    print "$slot";
}

      [download]
      
and there was no output....  Part of me was thingking it 
might be an issue with an ASCII file.  I tried opening the 
file using:


      binmode (STDOUT);

      [download]
      
and no difference...
[reply]
[d/l]
[select]
        I just tried it, substituting my while-loop for yours and it works for me. Maybe posting your entire script and test file would help .....

        ------
        We are the carpenters and bricklayers of the Information Age.

        Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

[reply]

        You want print "$slot\n";, since otherwise your prompt might cover things up if you don't print anything else (depending on your shell).

[reply]
[d/l]
Re: Extract field after keyword
by Not_a_Number (Prior) on Mar 19, 2004 at 20:01 UTC

    Not sure what your input file looks like, as you only give one 'field'. However, assuming it's like the __DATA__ below (even with varying whitespace), you could do something like this:

    use strict;
use warnings;

my $to_find = 'Pretty Woman';

while ( <DATA> ) {
   if ( /$to_find:\s*(\d+)/ ) {
      print "Slot for $to_find: $1\n";
   }
}

__DATA__
Label     Location                        Start Time  End Time
NKL0289   MSL6000 Trinity: 7              18:45       20:45
NKL0111   MSL7000 A Fish Called Wanda: 22 11:11       13:00
XKL0ABCC  MSL8000 Pretty Woman: 55        18:13       20:12

    [download]

    dave

[reply]
[d/l]
      The file is very basic... FILE:
      Report on Used Media

Cell Manager: Trinity.mydomain.com
Creation Date: 3/19/2004 10:05:17 AM

Label       Location       Pool Name Protection           Used [MB]   
+ Total [MB] Last Used
[NFK100L2] [MSL6000 Trinity:     7]  MSL6000              None        
+               0.06     204800.00 3/19/2004 10:04:2

      [download]
      All the code follows: 
      #$slotnumber=0;
$dpdrivloc = "Trinity";

open(DPSLOTFILE, "< c:\\test.txt") or die "Can't open test.txt: $!";

while (<DPSLOTFILE>) {
    if (/$dpdrivloc:\s*(\d+)/) {
    print "Slot for today is: $1\n";
}
}

    #system("c:\\ipbat.bat");

close DPSLOTFILE;

      [download]
[reply]
[d/l]
[select]

        So, it works? (It does for me.)

        Not sure from your reply. Do you still have a problem?

        dave

[reply]

Back to Seekers of Perl Wisdom