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Top Forums UNIX for Beginners Questions & Answers Expand Variables and Wildcards into another variable. Post 303035165 by MadeInGermany on Wednesday 15th of May 2019 02:32:39 PM
You see the difference with
Code:
echo "$file_path"

The quotes prevent the shell to do word-splitting on command arguments.

ls is an external command. The efficient per-line formatter is printf "%s\n" that 1. is a shell-builtin and 2. does no extra I/O.

What do you want to do with the $file_path?
It can make sense to not expand it too early. For example
Code:
file_path="${output_dir}/*MIGRATE*${city_name}*.out"
for f in $file_path

is smarter than
Code:
file_path=`ls ${output_dir}/*MIGRATE*${city_name}*.out`
for f in $file_path

 
Test Your Knowledge in Computers #726
Difficulty: Medium
Satoshi Yamashita is a pseudonym for the anonymous creator or creators of Bitcoin.
True or False?

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Plack::Session::Store::File(3pm)			User Contributed Perl Documentation			  Plack::Session::Store::File(3pm)

NAME
Plack::Session::Store::File - Basic file-based session store SYNOPSIS
use Plack::Builder; use Plack::Middleware::Session; use Plack::Session::Store::File; my $app = sub { return [ 200, [ 'Content-Type' => 'text/plain' ], [ 'Hello Foo' ] ]; }; builder { enable 'Session', store => Plack::Session::Store::File->new( dir => '/path/to/sessions' ); $app; }; # with custom serializer/deserializer builder { enable 'Session', store => Plack::Session::Store::File->new( dir => '/path/to/sessions', # YAML takes it's args the opposite order serializer => sub { YAML::DumpFile( reverse @_ ) }, deserializer => sub { YAML::LoadFile( @_ ) }, ); $app; }; DESCRIPTION
This implements a basic file based storage for session data. By default it will use Storable to serialize and deserialize the data, but this can be configured easily. This is a subclass of Plack::Session::Store and implements its full interface. METHODS
new ( %params ) The %params can include dir, serializer and deserializer options. It will check to be sure that the dir is writable for you. dir This is the directory to store the session data files in, if nothing is provided then "/tmp" is used. serializer This is a CODE reference that implements the serialization logic. The CODE ref gets two arguments, the $value, which is a HASH reference to be serialized, and the $file_path to save it to. It is not expected to return anything. deserializer This is a CODE reference that implements the deserialization logic. The CODE ref gets one argument, the $file_path to load the data from. It is expected to return a HASH reference. BUGS
All complex software has bugs lurking in it, and this module is no exception. If you find a bug please either email me, or add the bug to cpan-RT. AUTHOR
Stevan Little <stevan.little@iinteractive.com> COPYRIGHT AND LICENSE
Copyright 2009, 2010 Infinity Interactive, Inc. <http://www.iinteractive.com> This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. perl v5.12.4 2011-07-27 Plack::Session::Store::File(3pm)

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