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Full Discussion: Cant check empty string
Top Forums Shell Programming and Scripting Cant check empty string Post 302924079 by sea on Thursday 6th of November 2014 05:51:01 AM
Old 11-06-2014
Cant check empty string
Hello

So i have that script collection, in which i have a single script to create a configuration file.
In there, i have multiple occourences of something like this:
Code:
	prj_title=$(tui-read "What is the TITLE? ($prj_name):")
	[[ -z "$prj_title" ]] && prj_title="${prj_name/_/ }"

They all work as expected, if nothing is entred, it fills the variable with the default value.

However, for this it fails, and i fail to figure out why:
Code:
#
# Ask for a value, if value is empty, fill it with default
#

prj_tempdird="/tmp/${prj_name}_$ARCH"
prj_tempdir=""

#prj_tempdir=$(tui-read "What is the temp directory? ($prj_tempdird):")
read -p "What is the temp directory? ($prj_tempdird):" prj_tempdir

[[ -z "$prj_tempdir" ]] && prj_tempdir="$tempdird"
[[ -z $prj_tempdir ]] && prj_tempdir="$tempdird"
[[ "" = "$prj_tempdir" ]] && prj_tempdir="$tempdird"
[[ "" = "$(echo $prj_tempdir)" ]] && prj_tempdir="$tempdird"
[[ "" = "$(echo $prj_tempdir|tr -d [[:space:]])" ]] && prj_tempdir="$tempdird"
[[ -z "$(echo $prj_tempdir)" ]] && prj_tempdir="$tempdird"

echo "$prj_tempdir =! $prj_tempdird"

This is what i get:
Code:
:) ~ $ sh file1.txt
What is the temp directory? (/tmp/_):/home/TEMP
/home/TEMP =! /tmp/_               (this is 'expected')

+ ~ $ sh file1.txt
What is the temp directory? (/tmp/_):
 =! /tmp/_                        (this is NOT)
+ ~ $

This is what i expect:
Code:
+ ~ $ sh file1.txt
What is the temp directory? (/tmp/_):
/tmp/_ =! /tmp/_

Any ideas please?
Thank you in advance
 

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LEARN ABOUT DEBIAN

lr_environment

LR_ENVIRONMENT.IN(1)					  LogReport's Lire Documentation				      LR_ENVIRONMENT.IN(1)

NAME

       lr_environment - Export Lire configuration in shell script form

SYNOPSIS

       eval `lr_environment`

DESCRIPTION

       The lr_environment command is used to import the Lire configuration in Lire shell scripts.

       All of Lire configuration variables will be written in a format that can be evaled by the shell.

       Shell scripts don't usually have to use that command, since it is done by the defaults file sourced by each command.

       The old names used by when the configuration was done in shell script are also exported by this script for backward compatibility.

AUTHOR

	 Francis J. Lacoste <flacoste@logreport.org>

VERSION

       $Id: lr_environment.in,v 1.12 2006/07/23 13:16:33 vanbaal Exp $

COPYRIGHT

       Copyright (C) 2003 Stichting LogReport Foundation LogReport@LogReport.org

       This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by
       the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

       This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

       You should have received a copy of the GNU General Public License along with this program (see COPYING); if not, check with
       http://www.gnu.org/copyleft/gpl.html.

Lire 2.1.1							    2006-07-23						      LR_ENVIRONMENT.IN(1)
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