Defect Report concerning: IEEE Std. 1003.1c-1995, ISO/IEC 9945-1:1990 AMD 2 - Threads
Clause: 13.6.1.2
PASC Interpretation Ref: pasc-1003.1c-20
Topic: protocol attribute etc


This is an unapproved interpretation of PASC 1003.1c-1995, ISO/IEC 9945-1:1990 AMD 2 - Threads.

Use of the information contained in this unapproved document is at your own risk.

Last update: 30 March,1998


								1003.1c-95  #20

 _____________________________________________________________________________

	Interpretation Number:	XXXX
	Topic:               protocol attribute etc
	Relevant Sections:   13.6.1.2

Interpretation Request: (Defect Report)
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	Date: Tue, 16 Jul 1996 16:05:56 -0700
	From: "Scott J. Norton" <sjn@hpwssjn.cup.hp.com>

1) Section 13.6.1.2, page 128-129 D10, lines 581-587

What is the default value of the protocol attribute? 



2) Section 13.6.1.2, page 128-129 D10, lines 578-580, 595-606

PTHREAD_PRIO_PROTECT

This states that a) the priority of the locking thread shall raise its
priority to the mutex prioceiling and b) that prioceiling must be a valid
priority for SCHED_FIFO.

What happens if the locking thread is not SCHED_FIFO? Chances are pretty
good that the prioceiling value is not a valid priority for the scheduling
policy of the thread. Even if the thread is SCHED_RR the value may not
be valid. Do these functons imply that you must also change the scheduling
policy of the locking thread to SCHED_FIFO? If so, what happens if the
system defines SCHED_FIFO to have lower priorities than say SCHED_RR and
the thread is under SCHED_RR?


3) Section 13.6.1.2, page 128-129 D10, lines 590-594

PTHREAD_PRIO_INHERIT

This states that the blocking thread shall raise the priority of the thread
owning the mutex to equal that of the blocking thread.

Only the priority is being changed here. What happens if the threads are
in different scheduling policies? The new priority may not be valid in that
scheduling policy. Is it assumed that these functions also change the
policy of the thread if they are different?


Interpretation response
------------------------

This is a duplicate.  See PASC P1003.1c Interpretation #3, part 8.


Rationale
-------------
None.
Forwarded to Interpretations group: July 17th 1996
Finalised: Sep 4 1996