Answering questions that may arise related to the meaning of portions of an IEEE standard concerning specific applications.

IEEE Standards Interpretation for IEEE Std 1003.1™-1990 IEEE Standard for Information Technology--Portable Operating System Interfaces (POSIX®)

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Interpretation Request #88
PTHREAD_KEYS_MAX Relevant Sections: 2.8.5, PASC

Q1. How accurate does the value returned by sysconf(_SC_THREAD_KEYS_MAX) have to be?
Q2.Should an application be able to utilise the exact number returned ?
Q3.Is an implementation allowed to use some keys in its system libraries?
Q4.Is an implementation which claimed to provide a maximum of 256 (for example) thread specific data keys but actually could provide only 3 (to pick an extreme case) keys to an application (the rest being used by system libraries, etc) conforming?

Interpretation Response
The standard does not speak to this issue, and as such no conformance distinction can be made between alternative implementations based on this. This is being referred to the sponsor.

Rationale for Interpretation
Forwarded to Interpretations group: 19 Apr 1998 Proposed interpretation: 17 Jul 1998 Finalised: February 17 1999