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Top Forums Shell Programming and Scripting Bash: Pulling first and last character in string Post 302962326 by durden_tyler on Friday 11th of December 2015 08:14:07 PM
Old 12-11-2015
Sure, you're welcome!
If you have never programmed in Perl, then it might take some time to become comfortable with the language. But if you're going to do complex file processing, then learning a scripting language (any language: awk, Perl, Python, Ruby etc.) might be a good investment of your time.

A good way to learn Perl would be to start small and understand one concept at a time. For example,
- the shebang line (first line)
- the purpose of "use strict"
- hashes, arrays, scalars,
- how files are read, how they are written
- regular expression syntax
- functions like "lc", "int"
- operators like "defined" etc.

The Perl documentation is the best place to get information about these individual bits:
(1) perldoc.perl.org

Simon Cozen's online book is good for understanding programming in Perl (only the first 6 chapters should be enough):
(2) https://www.perl.org/books/beginning-perl/

The books by O'Reilly are well regarded:
(3) Learning Perl
(4) Intermediate Perl

And for the advanced Perl programmer:
(5) Programming Perl

Cookbooks are very interesting as well - they provide just enough information to get the job done. An online Perl cookbook is:
(6) PLEAC-Perl

And the published book is:
(7) Perl Cookbook, 2nd edition

This website has a list of Perl tutorials on the Internet and also mentions which ones are good and which ones are bad:
(8) Perl Tutorial Hub

However, besides reading about Perl, you'll also need to actually write programs to understand it.

=================

Having said that, there should be other forum members here who could post awk or plain Bash scripts for your problem, so keep an eye on this space.

Last edited by durden_tyler; 12-11-2015 at 09:20 PM..
This User Gave Thanks to durden_tyler For This Post:
 

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Parse::ErrorString::Perl(3pm)				User Contributed Perl Documentation			     Parse::ErrorString::Perl(3pm)

NAME
Parse::ErrorString::Perl - Parse error messages from the perl interpreter VERSION
version 0.15 SYNOPSIS
use Parse::ErrorString::Perl; my $parser = Parse::ErrorString::Perl->new; # or: my $parser = Parse::ErrorString::Perl->new(lang => 'FR') # to get localized explanations my @errors = $parser->parse_string($string_containing_stderr_output); foreach my $error(@errors) { print 'Captured error message "' . $error->message . '" in file ' . $error->file . ' on line ' . $error->line . " "; } METHODS
new(lang => $lang) Constructor. Receives an optional "lang" parameter, specifying that error explanations need to be delivered in a language different from the default (i.e. English). Will try to load "POD2::$lang::perldiag". parse_string($string) Receives an error string generated from the perl interpreter and attempts to parse it into a list of "Parse::ErrorString::Perl::ErrorItem" objects providing information for each error. SEE ALSO
splain ACKNOWLEDGEMENTS
Part of this module is based on code from splain. BUGS
Please report any bugs or feature requests to "bug-parse-errorstring-perl at rt.cpan.org", or through the web interface at <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Parse-ErrorString-Perl>. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes. SUPPORT
You can find documentation for this module with the perldoc command. perldoc Parse::ErrorString::Perl o RT: CPAN's request tracker <http://rt.cpan.org/NoAuth/Bugs.html?Dist=Parse-ErrorString-Perl> o AnnoCPAN: Annotated CPAN documentation <http://annocpan.org/dist/Parse-ErrorString-Perl> o CPAN Ratings <http://cpanratings.perl.org/d/Parse-ErrorString-Perl> o Search CPAN <http://search.cpan.org/dist/Parse-ErrorString-Perl/> AUTHORS
o Petar Shangov, "<pshangov at yahoo.com>" o Gabor Szabo <http://szabgab.com/> o Ahmad M. Zawawi <ahmad.zawawi@gmail.com> COPYRIGHT AND LICENSE
This software is copyright (c) 2010 by Petar Shangov. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself. perl v5.10.1 2010-11-29 Parse::ErrorString::Perl(3pm)
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