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Full Discussion: Bash variable expansion
Top Forums Shell Programming and Scripting Bash variable expansion Post 302997736 by jcdole on Thursday 18th of May 2017 04:03:25 PM
Old 05-18-2017
Bash variable expansion
Hello.
The file /etc/fstab contains
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 /                     ext4       noatime,discard,acl,user_xattr        1 1

I fill a variable
Code:
SOME_LINE=$( cat /etc/fstab | grep \/\..*ext4 | grep noatime,discard )

echo $SOME_LINE
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 / ext4 noatime,discard,acl,user_xattr 1 1

echo ${SOME_LINE}
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 / ext4 noatime,discard,acl,user_xattr 1 1

echo "$SOME_LINE"
Code:
UUID=957c3295-9944-1593-82e2-2b90dede4312 /                     ext4       noatime,discard,acl,user_xattr        1 1

I would like to know why The 3 outputs are not the same.

Thank you for helping.
Last edited by jcdole; 05-18-2017 at 06:51 PM..
 

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LEARN ABOUT DEBIAN

locale::script

Locale::Script(3perl)					 Perl Programmers Reference Guide				     Locale::Script(3perl)

NAME

       Locale::Script - standard codes for script identification

SYNOPSIS

	  use Locale::Script;

	  $script  = code2script('phnx');		      # 'Phoenician'
	  $code    = script2code('Phoenician'); 	      # 'Phnx'
	  $code    = script2code('Phoenician',
				 LOCALE_CODE_NUMERIC);	      # 115

	  @codes   = all_script_codes();
	  @scripts = all_script_names();

DESCRIPTION

       The "Locale::Script" module provides access to standards codes used for identifying scripts, such as those defined in ISO 15924.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default ISO 15924
       four-letter codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying scripts. The ones currently supported are:

       alpha
	   This is a set of four-letter (capitalized) codes from ISO 15924 such as 'Phnx' for Phoenician.

	   This code set is identified with the symbol "LOCALE_SCRIPT_ALPHA".

	   The Zxxx, Zyyy, and Zzzz codes are not used.

	   This is the default code set.

       numeric
	   This is a set of three-digit numeric codes from ISO 15924 such as 115 for Phoenician.

	   This code set is identified with the symbol "LOCALE_SCRIPT_NUMERIC".

ROUTINES

       code2script ( CODE [,CODESET] )
       script2code ( NAME [,CODESET] )
       script_code2code ( CODE ,CODESET ,CODESET2 )
       all_script_codes ( [CODESET] )
       all_script_names ( [CODESET] )
       Locale::Script::rename_script  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Script::add_script  ( CODE ,NAME [,CODESET] )
       Locale::Script::delete_script  ( CODE [,CODESET] )
       Locale::Script::add_script_alias  ( NAME ,NEW_NAME )
       Locale::Script::delete_script_alias  ( NAME )
       Locale::Script::rename_script_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Script::add_script_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Script::delete_script_code_alias  ( CODE [,CODESET] )
	   These routines are all documented in the Locale::Codes man page.

SEE ALSO

       Locale::Codes
       Locale::Constants
       http://www.unicode.org/iso15924/
	   Home page for ISO 15924.

AUTHOR

       See Locale::Codes for full author history.

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

COPYRIGHT

	  Copyright (c) 1997-2001 Canon Research Centre Europe (CRE).
	  Copyright (c) 2001-2010 Neil Bowers
	  Copyright (c) 2010-2011 Sullivan Beck

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

perl v5.14.2							    2011-09-26						     Locale::Script(3perl)
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