On Fri, Jan 29, 2016 at 12:08:38PM -0500, Chet Ramey wrote:
> On 1/27/16 5:59 AM, Stephane Chazelas wrote:
> > Hello,
> >
> > (tested with bash-4.3 and bash-2.05b)
> >
> > "time" is meant to time a pipeline. That generally includes
> > redirections of the last command in the pipeline, but in the
> > case of a subshell alone, the redirection is not timed(*) and
> > seems to affect the output of "time" itself.
>
> It's the way the bash implementation was from the start. If the command
> to be timed is run in a subshell and not part of a pipeline, the shell
> forks early and runs the command in a subshell. In this case, that
> subshell performs redirections before doing much of anything else.
>
> As you note below, some people have relied on it.
>
> Chet
> --
> ``The lyf so short, the craft so long to lerne.'' - Chaucer
> ``Ars longa, vita brevis'' - Hippocrates
> Chet Ramey, ITS, CWRU c...@case.edu http://cnswww.cns.cwru.edu/~chet/
>
This seems to be a related problem:
$ time (exec true) # doesn't print anything
$ time ( (exec true) ) # doesn't print anything
$ time ( ( (exec true) ) ) # doesn't print anything
$ time { (exec true); }
real: 0m0.001s, user: 0m0.000s, sys: 0m0.000s
---
xoxo iza
