Re: Namespace problem with pipe into a braced group

[Chris F.A. Johnson]

On Tue, 23 Feb 2010, t...@icada.com wrote:

> Configuration Information [Automatically generated, do not change]:
> Machine: x86_64
> OS: linux-gnu
> Compiler: gcc -I/usr/src/packages/BUILD/bash-3.1 
> -L/usr/src/packages/BUILD/bash-3.1/../readline-5.1
> Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' 
> -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-suse-linux-gnu' 
> -DCONF_VENDOR='suse' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL 
> -DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib   -O2 -fmessage-length=0 -Wall 
> -D_FORTIFY_SOURCE=2 -g -D_GNU_SOURCE -DRECYCLES_PIDS -Wall -pipe -g -fPIE 
> -fbranch-probabilities
> uname output: Linux t60 2.6.18.8-0.13-default #1 SMP Thu Nov 6 13:35:13 UTC 
> 2008 x86_64 x86_64 x86_64 GNU/Linux
> Machine Type: x86_64-suse-linux-gnu
> 
> Bash Version: 3.1
> Patch Level: 17
> Release Status: release
> 
> Description:
>       I would have expected the output to be 2 in both cases.  My mistake or 
> yours?  :-)
> 
> Repeat-By:
>       a=1; echo foo;{ a=2; }; echo $a         # output: 2
>       a=1; echo foo|{ a=2; }; echo $a         # output: 1
> 
>       Bug or feature?

   Standard behaviour; all components of a pipeline are executed in a
   subshell.

-- 
   Chris F.A. Johnson                          <http://cfajohnson.com>
   ===================================================================
   Author:
   Shell Scripting Recipes: A Problem-Solution Approach (2005, Apress)
   Pro Bash Programming: Scripting the GNU/Linux Shell (2009, Apress)