Re: redirection after braced block

[Matthew Woehlke]

clemens fischer wrote:
> Andreas Schwab wrote:
>
> > clemens fischer writes:
> >
> > > I have the following construct in a script:
> > >
> > >   ... a number of commands
> > >   {
> > >       ... a number of commands
> > >   } 2>&1 | ${prog_log} "${logfile}"
> > >
> > > It seems anything inside the braces is not seen by bash, and it
> > > doesn't show up in a "sh -x ..." trace, but ${prog_log} does.  I had
> > > debug echo's at the start of the block, they aren't triggered.
> > The trace goes to stderr, but you've just redirected it.
>
> yeah ok, but the commands really are not executed.  I have an option
> dry-run in the script, which sets "prog_log=true".  Then there are
> a bunch of verbose commands in the block, none of get touched.

This sort of construct seems to be working fine for me. Note that the 
contents of the block are executed in a subshell, and using 'true' as 
prog_log will suppress both stdout and stderr, as set up (though you 
might get a broken pipe error). So unless the commands in the block have 
side effects observable outside of the script, you won't know whether or 
not they execute.

--
Matthew
Please do not quote my e-mail address unobfuscated in message bodies.
--
Q: Why doesn't Fedora provides ponies? -- Benny Amorsen
A: Because they're too big to fit in the bikeshed. -- Mat Booth