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

Hello,

Any idea how to parse this file of 4 columns and populate and array with the data? 

DATA:

0x130005d   1.253.54.1_MIB  0x230f0    SNMP        
0x130009c                   0x1006b    SnmpPif

($MHandle,$MName,$MTypeHnd,$MTypeName)=split(/\s/g,$_);

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Doesn't seem to work with the empty 2nd column

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Re: File parse
by myocom (Deacon) on Dec 05, 2002 at 18:41 UTC

    This is a perfect job for unpack. The following test code should prove helpful:

    use strict;
while (<DATA>) {
    chomp;
    my @array = unpack("A12A16A11A*", $_); # @array has 4 elements now
    print map("'$_'\n", @array);
}

__DATA__
0x130005d   1.253.54.1_MIB  0x230f0    SNMP        
0x130009c                   0x1006b    SnmpPif

    [download]
    "One word of warning: if you meet a bunch of Perl programmers on the bus or something, don't look them in the eye. They've been known to try to convert the young into Perl monks." - Frank Willison
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[d/l]
Re: File parse
by BrowserUk (Patriarch) on Dec 05, 2002 at 18:49 UTC

    Effectively you are passing fixed length records. Try unpack. 

    #! perl -slw
use strict;

while (<DATA>) {
    my @data = unpack 'A9 xx A14 xx A7 xxx A*', $_;
    { local $,='|', print @data; }
}

__DATA__
0x130005d  1.253.54.1_MIB  0x230f0   SNMP
0x130009c                  0x1006b   SnmpPif

# Gives
C:\test>217843
0x130005d|1.253.54.1_MIB|0x230f0|SNMP
0x130009c||0x1006b|SnmpPif

C:\test>

    [download]

    Okay you lot, get your wings on the left, halos on the right. It's one size fits all, and "No!", you can't have a different color.
    Pick up your cloud down the end and "Yes" if you get allocated a grey one they are a bit damp under foot, but someone has to get them.
    Get used to the wings fast cos its an 8 hour day...unless the Govenor calls for a cyclone or hurricane, in which case 16 hour shifts are mandatory.
    Just be grateful that you arrived just as the tornado season finished. Them buggers are real work.

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Re: File parse
by fruiture (Curate) on Dec 05, 2002 at 18:39 UTC

    Yep, this won't work if the file format is defined to have whitespace-seperated columns.

    However, if you change the definition, it woll work. For example you define the columns by starting-position and width.

    my @columns = (
      [ 0 , 9 ], # position,width
      [ 13, 14],
      # ...
);
while( <$the_file> ){
   chomp;
   my @data = ();
   for my $spec ( @columns ){
      push @data , substr($_,@$spec)
   }
   print join('|',@data),"\n";
}

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    Programming is a question of definition

    --
    http://fruiture.de
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