Fixing Posix semaphores

Joe Kelsey joe at
Mon Dec 13 14:09:28 PST 2004

I have a desire to fix posix semaphores in at least 5.3.  The current
implementation doesn't actually follow the "spirit" of the standard,
even though it technically qualifies in a somewhat degraded sense.  I
refer to the fact that the current implementation treats posix
semaphores as completely contained inside the kernel and essentially
divorced from the filesystem.  The true "spirit" of the standard places
the semaphores directly in the file system, similar to named pipes.
However the current implementation treats the supplied "name" as a
14-character identifier, required to begin with a slash and contain no
other slashes.  Pretty weak.

Well, in order to fix this, we need to add file system code and come up
with a new type.  I currently have some time to spend on something like
this and am willing to put in whatever effort it takes.  Does anyone
want to add their own ideas or requirements?

I currently run 5.3, but I suppose I could think about running current
at some point in the future.


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