dyer@spdcc.UUCP (04/11/87)
I am not sure that performing a lockf on the active file is such a
good idea, at least given the interpretation of the lockf call by
SCO XENIX. Rather than simply having all cooperating processes
which use lockf block on an attempt to lock, which is arguably the
correct interpretation of the SVID as I read it, SCO XENIX blocks
any process which tries to open, read from or write to the locked file,
leading to rather confusing behavior, especially when a process which
takes a long time locks the active file, such as expire. The net effect
is that the entire news system is locked up, causing such programs such
as 'rn' and 'readnews' to hang until the expire completes.
Of course, one solution is simply not to use lockf, but perhaps a
simpler approach is for expire and inews to invoke lockf on a file which is
used only by those two programs for synchronization. Such an approach
works on both brain-dead and proper-SVID System V implementations.
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Steve Dyer
dyer@harvard.harvard.edu
dyer@spdcc.COM aka {ihnp4,harvard,linus,ima,bbn,halleys}!spdcc!dyer