controlling runaway procedures at the Magik prompt

Have you ever run a procedure at the Magik prompt and it kept running and the only way you could terminate it was to close the Magik session? There is another way!

I was working on a procedure today that parses the results of a Relational Integrity Check and summarizes the errors by rwo_type. I wasn't sure how long it would take to run, so I forked the procedure in a new thread.

For illustration here, I have created a procedure that runs an endless loop. If you ran this at the Magik prompt, you would need to terminate the session in order to end the loop. To avoid this hassle, I have forked the procedure in a new thread using fork_at(). You can review the public comments for this method in the class browser to learn about the valid arguments.

MagikSF> th << _proc()
_loop

_endloop 
_endproc.fork_at(5)
$

Now it is easy to query the thread to see if it is running or not...

MagikSF> th.status_description
$
"runnable"

You can pause the thread...

MagikSF> th.suspend()
$
thread(unnamed suspended 5)
MagikSF> th.status_description
$
"suspended"

You can resume a paused thread...

MagikSF> th.resume()
$
thread(unnamed runnable 5)
MagikSF> th.status_description
$
"runnable"

Or you can finally terminate the thread...

MagikSF> th.kill()
$
thread(unnamed runnable 5)
MagikSF> th.status_description
$
"terminated"