What is $[ ] ?

[Marc Herbert]

Hi,


 I could not find the dollar square brackets $[ ] expansion documented
in the manual. Is it the same as $(( )) ?

Cheers,

Marc



Le 22/03/2010 13:13, tbartdev@gmx-topmail.de a écrit :
> Configuration Information [Automatically generated, do not change]:
> Machine: i686
> OS: linux-gnu
> Compiler: i686-pc-linux-gnu-gcc
> Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='i686' 
> -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i686-pc-linux-gnu' 
> -DCONF_VENDOR='pc' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL 
> -DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib  
> -DDEFAULT_PATH_VALUE='/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin'
>  -DSTANDARD_UTILS_PATH='/bin:/usr/bin:/sbin:/usr/sbin' 
> -DSYS_BASHRC='/etc/bash/bashrc' -DSYS_BASH_LOGOUT='/etc/bash/bash_logout' 
> -DNON_INTERACTIVE_LOGIN_SHELLS -DSSH_SOURCE_BASHRC -O2 -march=core2 
> -mfpmath=sse -msse4.1 -fomit-frame-pointer -pipe
> uname output: Linux blackknight 2.6.31-gentoo-r6 #1 SMP PREEMPT Mon Nov 30 
> 19:03:35 CET 2009 i686 Intel(R) Core(TM)2 Duo CPU T9300 @ 2.50GHz 
> GenuineIntel GNU/Linux
> Machine Type: i686-pc-linux-gnu
> 
> Bash Version: 4.0
> Patch Level: 35
> Release Status: release
> 
> Description:
>     The man page seems to be wrong regarding the handling of numbers with 
> different bases. It states one has to use [base#]n although it seems to be 
> [base#n] that needs to be used...
>     (I know I do not have the latest bash, but with 4.1 it is the same in the 
> man page.)
> 
> Repeat-By:
>     blackknight ~ $ echo $[2#]10
>     010
>     blackknight ~ $ echo $[2#10]
>     2
> 
> Fix:
>     Correct the man page