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SEM_VALUE_MAX too big?
I needed sysconf(_SC_SEM_VALUE_MAX) and found that it is not yet
supported in NetBSD-current but that there is SEM_VALUE_MAX defined in
#define SEM_VALUE_MAX (~0U)
If we ever want to support sysconf(_SC_SEM_VALUE_MAX), there will be the
slight difficulty that sysconf() returns "long" and our value for
SEM_VALUE_MAX is too big for a long.
As far as I could find, some other systems use a lower value for
SEM_VALUE_MAX (found through a web search):
Linux uses "(int) (~0U >>1)" (according to the LSB definition)
Solaris seems to use 2147483647 (= INT_MAX)
OpenSolaris uses INT_MAX
Darwin uses 32767
FreeBSD uses the same value as NetBSD, (~0U)
OpenBSD uses UINT_MAX
At the moment, the high value prevents us from supporting
sysconf(_SC_SEM_VALUE_MAX), assuming that we do _not_ want to have two
different values for the same thing.
What would we loose if we lowered the value of SEM_VALUE_MAX by half?
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