Re: Is fork() broken in octave 5.1 ?

[John W. Eaton]

On 9/26/19 1:42 PM, Mike Miller wrote:
> On Thu, Sep 26, 2019 at 19:27:55 +0200, Kay Nick wrote:
> > Nevertheless I find this behavior not intuitive... What is the reason
> > for preventing fork() from being used in a simple script?
>
> It is related to this (still open) bug report:
> https://savannah.gnu.org/bugs/?45625

Yes, the check was added to prevent simple calls to fork at the command 
line from creating two copies of Octave both competing for input from 
the terminal and possibly confusing users.  Once this situation occurs, 
it can be difficult to recover from without killing the session.

The check that was added doesn't distinguish between the command line 
and a script evaluated from the command line.  A script executes in the 
scope of the caller and the check was for execution at the top-level 
scope rather than checking the depth of the call stack.

Maybe we could change the condition so that it will allow fork if it is 
executed from a script but not directly from the command line.

jwe