add a working procedure
Adds a working procedure. Returns an identifier for the working procedure
that is required by VtRemoveWorkProc if you subsequently remove it.
A working procedure is called
whenever the application is sitting idle. After the working procedure
is called, control goes back to the main loop. If there are still no
events in the queue, the working procedure is called again, and is
repeatedly called whenever there are no other events happening
(such as buttons being pressed, text being entered, and so on). If more than
one working procedure is added via subsequent
calls to VtAddWorkProc, then
they are called one at a time, in a round robin.
A common use for working procedures is when the application needs to
do some work that the user can cancel out of. The working procedure
would do its work in short time-slices, keeping track of its
state. Consequently, if the user cancels the operation, cleanup can be done
that is dependent on the value of the state variables.
© 2003 Caldera International, Inc. All rights reserved.
SCO OpenServer Release 5.0.7 -- 11 February 2003