I find that if I add comments as I go, writing code is much easier. Here's some code that works for me:

#!/usr/bin/perl

use strict;

{
    #  Get filename, starting regex and stopping regex
    #  from the command line.

    my ( $filename, $start, $stop ) = @ARGV;

    #  Check the inputs, open the file.

    die "ERROR: Need to define start and stop arguments."
      unless ( defined($start) && defined($stop) );
    open(INPUT, $filename) or
      die "Unable to open $filename: $!";

    #  Loop through the file, looking for the starting
    #  regexp and skipping lines till then.

    while(<INPUT>) {
      if ( /$start/ ) {

        #  Found the matching line! Print it, and start
        #  looking for the stopping regexp.

        print;
        while(<INPUT>) {

          #  If we found the stopping regexp, drop out
          #  of this loop; otherwise, print a line and
          #  keep going.

          if ( /$stop/ ) { last; } else { print; }
        }
      }
    }
    close(INPUT);
}

[download]

I've grabbed all of the arguments from the command line right at the start -- this is far easier than trying to remember what's still left to be read in later.

The advantage to this code is that it will find multiple occurrences of start/stop in a single file.

Alex / talexb / Toronto

"Groklaw is the open-source mentality applied to legal research" ~ Linus Torvalds

In reply to Re^3: Parse a block of text by talexb
in thread Parse a block of text by annie06

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