Re: Command substitution with null bytes generates warning

[Chet Ramey]

On 9/16/16 1:51 AM, Eric Pruitt wrote:

> Bash Version: 4.4
> Patch Level: 0
> Release Status: release
> 
> Description:
>       I have a script that execute `if [[ "$(<"/proc/$1/cmdline")" = tmux* 
> ]];`.
>       All /proc/*/cmdline include null bytes, and as of Bash 4.4, this 
> results in
>       a warning being spewed on stderr which did not happen in Bash 4.3.
> 
> Repeat-By:
>       echo "$(<"/proc/$$/cmdline")"
> 
> Fix:
>       Is this even an intentional change? I looked at some of the other
>       internal_warning invocations, and they were commented out using "#if 0 
> ...
>       #endif."

Try the attached patch, which reduces the number of warnings to 1 per call
to command substitution.

Chet
-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/

comsub-nullbyte.patch
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