Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Variable assignments specified with eval shell built-in
Top Forums UNIX for Advanced & Expert Users Variable assignments specified with eval shell built-in Post 302486390 by Scrutinizer on Saturday 8th of January 2011 06:51:07 AM
Old 01-08-2011
Variable assignments specified with eval shell built-in
According to the POSIX specifications eval is a special shell built-in, which should imply that variable assignments specified together with it should remain in effect after the built-in completes. Thus one would expect IFS to be changed after this:
Code:
var=$'a\nb c'
$ IFS=$'\n' eval '
for i in $var; do
  echo "$i"
done'
a
b c

But it isn't:
Code:
$ set | grep ^IFS
IFS=$' \t\n'

Last edited by fpmurphy; 01-08-2011 at 11:43 AM.. Reason: fixed link
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

eval a variable that has a .

Hi, Is there any way that I can eval the following - eval abc.csv=def.csv I am getting the - bash: command not found error. thanks. (3 Replies)
Discussion started by: ttshell
3 Replies

2. Shell Programming and Scripting

How to assign eval value as Variable..

Im facing problem in assigning value of eval array variable as normal variable.. x=0 eval DATA${x}="FJSVcpcu" x=`expr $x + 1` eval DATA${x}="FJSVcsr" if x=0, type -> eval echo \$DATA$x , its give me FJSVcpcu i want assign this value into an variable as variable=`eval echo... (3 Replies)
Discussion started by: neruppu
3 Replies

3. UNIX for Dummies Questions & Answers

built in variable to hold the name of therunning script...

Hi, I have multiple functions that can be called by any shell script. These functions have inbuilt echo statements to logs their activity into a log file. When I run multiple shell scripts that call these functions, they all log into the same log file and I am not able to differentiate which... (2 Replies)
Discussion started by: new_learner
2 Replies

4. Shell Programming and Scripting

Passing eval value to a variable

Hello, I have a script that does an scp to a server and then gets the number of process running on that server, the o/P should be stored in a variable for further processing eval `echo "ssh -q $Infa_user@$host 'csh -c $CMD '"` where CMD="ps -ef | grep -i ${INFA_REPO} | grep -v grep | wc... (2 Replies)
Discussion started by: amit1_x
2 Replies

5. Shell Programming and Scripting

eval and variable assignment

Hi, i have an issue with eval and variable assignment. 1) i have a date value in a variable and that date is part of a filename, var1=20100331 file1=${var1}-D1-0092.xml.zip file2=${var2}-D2-0092.xml.zip file3=${var3}-D3-0092.xml.zip i am passing the above variables to a script via... (11 Replies)
Discussion started by: mohanpadamata
11 Replies

6. Shell Programming and Scripting

assignment to variable from eval command

Hi Gurus, I am having 2 parameters as below parm1=value1 parm2=parm1 I want to evaluate parm1 value using eval echo \$$parm2 and later i want to assign this value to other variable which i will be using in if statement like : if ]; then do this....... fi could you please suggest... (5 Replies)
Discussion started by: k_vikash
5 Replies

7. Shell Programming and Scripting

awk built-in variable for input file

Hi guys, Does awk have a built-in variable which I can use to display the input file it's currently reading? I'm currently concatenating multiple files using awk and later on do some parsing. But for now, I want to add an extra column in the main output data file - basically putting in the... (3 Replies)
Discussion started by: Det7
3 Replies

8. Shell Programming and Scripting

Newline in my script-built shell variable

Hi all, I'm not exactly a shell script guru, so this is probably a very silly question and I'm not seeing the point, but you know, sometimes it happens... I have this script which adds entries to local arp cache using it to find the corresponding IP address. # export MAC=00:25:90:34:3d:f2... (16 Replies)
Discussion started by: micantox
16 Replies

9. Shell Programming and Scripting

'eval' used in variable assignment

pattern1=book { x=1 eval echo \$pattern$x } book (this is the output) But when I assign a variable to the output of the eval it doesn't work unless I prefix 2 times backslash before $ as shown below. { a=`eval echo \\$pattern$x` echo $a } book Why here twice "\" has to be... (3 Replies)
Discussion started by: ravisingh
3 Replies

10. Shell Programming and Scripting

Safe way to eval variable declarations?

Is there a safe way to evaluate variable declarations within a script whether they come from a .conf file, user input, or stdin? Example .conf file: server=ftp.xxxx.com port=21 user="$USER" # Hopefully allow this type of substitution domain="$DOMAIN" server="$(malicious... (4 Replies)
Discussion started by: Michael Stora
4 Replies

LEARN ABOUT MOJAVE

locale::codes::langext5.18

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

NAME

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

SYNOPSIS

	  use Locale::Codes::LangExt;

	  $lext = code2langext('acm');		       # $lext gets 'Mesopotamian Arabic'
	  $code = langext2code('Mesopotamian Arabic'); # $code gets 'acm'

	  @codes   = all_langext_codes();
	  @names   = all_langext_names();

DESCRIPTION

       The "Locale::Codes::LangExt" module provides access to standard codes used for identifying language extensions, such as those as defined in
       the IANA language registry.

       Most of the routines take an optional additional argument which specifies the code set to use. If not specified, the default IANA language
       registry codes will be used.

SUPPORTED CODE SETS

       There are several different code sets you can use for identifying language extensions. 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 = code2langext('acm','alpha');
	  $lext = code2langext('acm',LOCALE_LANGEXT_ALPHA);

       The codesets currently supported are:

       alpha
	   This is the set of three-letter (lowercase) codes from the IANA language registry, such as 'acm' for Mesopotamian Arabic.

	   This is the default code set.

ROUTINES

       code2langext ( CODE [,CODESET] )
       langext2code ( NAME [,CODESET] )
       langext_code2code ( CODE ,CODESET ,CODESET2 )
       all_langext_codes ( [CODESET] )
       all_langext_names ( [CODESET] )
       Locale::Codes::LangExt::rename_langext  ( CODE ,NEW_NAME [,CODESET] )
       Locale::Codes::LangExt::add_langext  ( CODE ,NAME [,CODESET] )
       Locale::Codes::LangExt::delete_langext  ( CODE [,CODESET] )
       Locale::Codes::LangExt::add_langext_alias  ( NAME ,NEW_NAME )
       Locale::Codes::LangExt::delete_langext_alias  ( NAME )
       Locale::Codes::LangExt::rename_langext_code  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangExt::add_langext_code_alias  ( CODE ,NEW_CODE [,CODESET] )
       Locale::Codes::LangExt::delete_langext_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.iana.org/assignments/language-subtag-registry
	   The IANA language subtag registry.

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::LangExt(3pm)
All times are GMT -4. The time now is 04:34 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy