Re: why does "jobs | wc" not work?

[Vincent Lefevre <vincent@vinc17.org>]

In article <20021126104930.GE1937@gmx.de>,
   Dominik Vogt <dominik.vogt@gmx.de> wrote:
> There seems to be a strange bug with the jobs command in
> zsh-4.0.4.  It seems that the output of the jobs command refuses
> to go into a pipe.

> This works:

>   $ sleep 1000 &
>   [1] 6262
>   $ jobs > foo
>   $ wc foo
>         1       5      29 foo   <--

> But this does not:

>   $ sleep 1000 &
>   [1] 6262
>   $ jobs | wc
>         0       0       0       <-- ?

> And also:

>   $ echo `jobs`

>   $

> Is there a specific reason why jobs generates no output when
> running in a pipe?

Because jobs is executed in a subshell?

This is not the case with jobs > foo. "true | jobs" is also OK.

> Note:  In pdksh and bash (as bash and sh), jobs works as I would
> expect; csh and tcsh work like zsh.

AFAIK, shells do not implement the pipe and jobs in the same way.

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