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.

Other users have expectations that differ from yours.  I received messages
reporting the the bash-4.3 behavior (the longtime bash behavior) as a bug.
Warning the user that bash discards some characters from the command
substitution output seemed like the course that would let everyone know
what's happening regardless of their expectations.

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/