[lug] bash -x script_to_debug

[rm at mamma.varadinet.de]

On Sun, Apr 01, 2001 at 03:11:20AM -0600, D. Stimits wrote:
> Bob Collins wrote:
> > 
> > Is there a way to capture the output sent to the screen when
> > running a script like below?
> > 
> > bash -x script_to_debug
> > 
> > --
> >    Regards, Bob Collins
> > Computers are useless.  They can only give you answers.
> >                 -- Pablo Picasso
> 
> The "tee" command is nice for this. For example, if it is just standard
> out (no standard error):
> bash -x script_to_debug | tee FileNameToLogTo.txt

Won't work like that. You'll only catch the output of
the script, _not_ the debugging messages of bash
which are sent to stderr (file descriptor 2).
You have two options:

 - redirect the output of bash

   bash -x script_to_debug 2>log.txt

 - redirect both the output of bash as well
   as the output of the script (and the error
   messages of the script)

   bash -x script_to_debug >log.txt 2>&1

 - record the whole session with 'script'

  $ script log.txt
    Script started, file is log.txt
  $ bash -x script_to_debug
  + ....
    ....
  $ ^D
  $ Script done, file is log.txt

  If you don't give a filename to script it wil save 
  all output to the file 'typescript'. You need to
  enter Ctr-D to stop script from recording the session.


 Ralf