kcwong@ssd.kodak.com (K.C. Wong) (06/21/91)
The Xview programming manual says not to use wait() and wait3() calls.
Is it safe to use wait4() calls?
I found that some times using the notify_set_wait3_func() call not
practical. It throws my processing off logically.
For example, on a sparc station 2, I would like to find out if the
floppy is in the drive before doing any writing by making the
system call "eject -q" (which takes only a fraction of a second).
Using the callback scheme with notify_set_wait3_func() is inconvenient
at best.
I would like to do,
pid = fork()
in child, exec ("eject -q")
in parent, wait4(pid,...) non-blocking in a loop,
and check the exit code value.
if exit code values is 0 (=> floppy is in)
perform something.
Since the call I exec takes such a short time, could I do the above?
I don't want to handle any events during these processing.
Your input is very welcome.
Regards,
K.C.Wong
kcwong@ssd.kodak.com
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