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PTHREAD_GETCONCURRE... FreeBSD Library Functions Manual	PTHREAD_GETCONCURRE...

NAME
     pthread_getconcurrency, pthread_setconcurrency -- get or set level	of
     concurrency

LIBRARY
     POSIX Threads Library (libpthread,	-lpthread)

SYNOPSIS
     #include <pthread.h>

     int
     pthread_getconcurrency(void);

     int
     pthread_setconcurrency(int	new_level);

DESCRIPTION
     The pthread_getconcurrency() function allows an application to inform the
     threads implementation of its desired concurrency level, new_level.  The
     actual level of concurrency provided by the implementation	as a result of
     this function call	is unspecified.	 If new_level is zero, it causes the
     implementation to maintain	the concurrency	level at its discretion	as if
     pthread_setconcurrency() was never	called.	 The pthread_getconcurrency()
     function returns the value	set by a previous call to the
     pthread_setconcurrency() function.	 If the	pthread_setconcurrency() func-
     tion was not previously called, this function returns zero	to indicate
     that the implementation is	maintaining the	concurrency level.  When an
     application calls pthread_setconcurrency(), it is informing the implemen-
     tation of its desired concurrency level.  The implementation uses this as
     a hint, not a requirement.

RETURN VALUES
     If	successful, the	pthread_setconcurrency() function returns zero.	 Oth-
     erwise, an	error number is	returned to indicate the error.	 The
     pthread_getconcurrency() function always returns the concurrency level
     set by a previous call to pthread_setconcurrency().  If the
     pthread_setconcurrency() function has never been called,
     pthread_getconcurrency() returns zero.

ERRORS
     The pthread_setconcurrency() function will	fail if:

     [EINVAL]		The value specified by new_level is negative.

     [EAGAIN]		The value specified by new_level would cause a system
			resource to be exceeded.

APPLICATION USAGE
     Use of these functions changes the	state of the underlying	concurrency
     upon which	the application	depends.  Library developers are advised to
     not use the pthread_getconcurrency() and pthread_setconcurrency() func-
     tions since their use may conflict	with an	application's use of these
     functions.

STANDARDS
     The pthread_getconcurrency() and pthread_setconcurrency() functions con-
     form to Version 2 of the Single UNIX Specification	(``SUSv2'').

FreeBSD	9.3			April 11, 2003			   FreeBSD 9.3

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | APPLICATION USAGE | STANDARDS

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