On Fri, Feb 12, 2016 at 10:22 AM, Ulrich Windl <
ulrich.wi...@rz.uni-regensburg.de> wrote:
> Configuration Information [Automatically generated, do not change]:
> Machine: x86_64
> OS: linux-gnu
> Compiler: gcc -I/home/abuild/rpmbuild/BUILD/bash-4.2
> -L/home/abuild/rpmbuild/BUILD/bash-4.2/../readline-6.2
> 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 -fmessage-length=0
> -grecord-gcc-switches -O2 -Wall -D_FORTIFY_SOURCE=2 -fstack-protector
> -funwind-tables -fasynchronous-unwind-tables -g -D_GNU_SOURCE
> -DRECYCLES_PIDS -Wall -g -Wuninitialized -Wextra -Wno-unprototyped-calls
> -Wno-switch-enum -Wno-unused-variable -Wno-unused-parameter
> -ftree-loop-linear -pipe -DBNC382214=0 -fprofile-use
> uname output: Linux pc 4.1.15-8-default #1 SMP PREEMPT Wed Jan 20 16:41:00
> UTC 2016 (0e3b3ab) x86_64 x86_64 x86_64 GNU/Linux
> Machine Type: x86_64-suse-linux-gnu
>
> Bash Version: 4.2
> Patch Level: 47
> Release Status: release
>
> Description:
> `${PARAMETER:OFFSET}' does not work for negative offset; the complete
> parameter value is substituted
>
> The bug goes back to at least bash 3.2...
>
> Repeat-By:
> "X=ABC; echo ${X:-2}" outputs "ABC", and not "BC"
>
There is an ambiguity between ${param:-default} and ${param:n:m} when n is
negative
${X:(-2)} or ${X: -2} (with space) are possible workarounds
