Re: Reprise: external pager quitting kills standard error

[John W. Eaton]

On 30-Jan-2005, Dmitri A. Sergatskov <address@hidden> wrote:

| >> octave:2> junk = ones(100)
| >> warning: connection to external pager (pid = 18461) lost --
| >> warning: attempting to finish pending computations...
| >> octave:3> bogus
| 
| I just have noticed the difference between your output 
| (and  "Daniel J. Peng" <dpeng at CS dot Princeton dot EDU>
| from the links) and mine:
| 
| octave:2> ones(2500,25)
| warning: connection to external pager (pid = 26872) lost --
| warning: attempting to finish pending computations...
| warning: broken pipe
| octave:3> error("aoeo")
| error: aoeo
| octave:3> junk = ones(1000)
| warning: connection to external pager (pid = 26874) lost --
| warning: attempting to finish pending computations...
| warning: broken pipe
| octave:4> bogus
| error: `bogus' undefined near line 4 column 1
| octave:4>
| 
| I have an extra line:
| 
| warning: broken pipe
| 
| I have no idea what it might mean...

It means that the program that was reading from the pipe (usually
"less") quit while there was still data left to read from the pipe.

I can reproduce the problem of error messages being lost if I set
page_output_immediately to a nonzero value:

  octave:1> page_output_immediately = 1
  page_output_immediately = 1
  octave:2> bogus
  error: `bogus' undefined near line 2 column 1
  octave:3> ones (1000,10)
  warning: connection to external pager (pid = 4090) lost --
  warning: attempting to finish pending computations...

  octave:3> bogus

I am typing 'q' to exit the pager as soon as the first page is
displayed.  If I page forward to the end then back to the beginning
(or anywhere) and then quit, things seem to work normally.  It is only
when the connection to the pager is lost in this way that I see the
error.

So yes, there does seem to be a bug here.

jwe