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Full Discussion: Command behaves different in script and on prompt
Operating Systems AIX Command behaves different in script and on prompt Post 302445880 by bakunin on Tuesday 17th of August 2010 05:49:16 AM
Old 08-17-2010
Quote:
Originally Posted by panchpan
Code:
input=`head -1 /tmp/tuxob.lst | awk '{print $NF}'`

If above is the script, then how do I put if conditions. i.e. If $input = '*****' do something.
First off, you don't need any if-contructions. You should quote your variables regardless of them containing something which has to be quoted or not, because even if said variables normally don't have a content which has to be quoted they might do so occasionally and a script shouldn't work "most of the times", but always.

In programming caution sometimes helps but never hurts, so be as cautious as possible.

Secondly, you shouldn't use the backticks any more: they are supported only for backwards compatibility purposes. Use the "$(...)" instead:

Code:
input="$(head -1 /tmp/tuxob.lst | awk '{print $NF}')"

Thirdly, the command only fills a variable with some content - in this case some asterisks. No shell expansion is done here. It is probably done when you subsequently try to display the variables contents. THIS is the place where you have to protect your variable from being expanded by the shell:

Code:
input="$(head -1 /tmp/tuxob.lst | awk '{print $NF}')"
echo $input         # will be expanded
echo "$input"       # will not be expanded

Btw.: if the only thing you want to do is to display it, you don't even need the variable:

Code:
echo "$(head -1 /tmp/tuxob.lst | awk '{print $NF}')"  # will not be expanded
echo $(head -1 /tmp/tuxob.lst | awk '{print $NF}')    # will be expanded

I hope this helps.

bakunin
 

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LEARN ABOUT MOJAVE

locale::codes::langfam5.18

Locale::Codes::LangFam(3pm)				 Perl Programmers Reference Guide			       Locale::Codes::LangFam(3pm)

NAME

       Locale::Codes::LangFam - standard codes for language extension identification

SYNOPSIS

	  use Locale::Codes::LangFam;

	  $lext = code2langfam('apa');		       # $lext gets 'Apache languages'
	  $code = langfam2code('Apache languages');    # $code gets 'apa'

	  @codes   = all_langfam_codes();
	  @names   = all_langfam_names();

DESCRIPTION

       The "Locale::Codes::LangFam" module provides access to standard codes used for identifying language families, such as those as defined in
       ISO 639-5.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 639-5
       language family codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying language families. A code set may be specified using either a name, or a
       constant that is automatically exported by this module.

       For example, the two are equivalent:

	  $lext = code2langfam('apa','alpha');
	  $lext = code2langfam('apa',LOCALE_LANGFAM_ALPHA);

       The codesets currently supported are:

       alpha
	   This is the set of three-letter (lowercase) codes from ISO 639-5 such as 'apa' for Apache languages.

	   This is the default code set.

ROUTINES

       code2langfam ( CODE [,CODESET] )
       langfam2code ( NAME [,CODESET] )
       langfam_code2code ( CODE ,CODESET ,CODESET2 )
       all_langfam_codes ( [CODESET] )
       all_langfam_names ( [CODESET] )
       Locale::Codes::LangFam::rename_langfam  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Codes::LangFam::add_langfam  ( CODE ,NAME [,CODESET] )
       Locale::Codes::LangFam::delete_langfam  ( CODE [,CODESET] )
       Locale::Codes::LangFam::add_langfam_alias  ( NAME ,NEW_NAME )
       Locale::Codes::LangFam::delete_langfam_alias  ( NAME )
       Locale::Codes::LangFam::rename_langfam_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangFam::add_langfam_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangFam::delete_langfam_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes::API man page.

SEE ALSO

       Locale::Codes
	   The Locale-Codes distribution.

       Locale::Codes::API
	   The list of functions supported by this module.

       http://www.loc.gov/standards/iso639-5/id.php
	   ISO 639-5 .

AUTHOR

       See Locale::Codes for full author history.

       Currently maintained by Sullivan Beck (sbeck@cpan.org).

COPYRIGHT

	  Copyright (c) 2011-2013 Sullivan Beck

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.18.2							    2013-11-04					       Locale::Codes::LangFam(3pm)
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