pthread_setconcurrency(3)pthread_setconcurrency(3)NAMEpthread_setconcurrency - Changes the value of the concurrency level
global variable for this process
SYNOPSIS
#include <pthread.h>
int pthread_setconcurrency(
int level );
LIBRARY
DECthreads POSIX 1003.1c Library (libpthread.so)
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
IEEE Std 1003.1c-1995, POSIX System Application Program Interface
PARAMETERS
New value for the concurrency level for this process.
DESCRIPTION
This routine stores the value specified in the level argument in the
“concurrency level” global setting for the calling thread's process.
Because DECthreads automatically manages the concurrency of all threads
in a multithreaded process, DECthreads ignores this concurrency level
value.
The concurrency level value has no effect on the behavior of a multi‐
threaded program that uses DECthreads. This routine is provided for
Single UNIX Specification, Version 2 source code compatibility and has
no other effect when called.
After calling this routine, subsequent calls to the pthread_getconcur‐
rency(3) routine return the same value, until another call to
pthread_setconcurrency(3) changes that value.
The initial concurrency level is zero (0), indicating that DECthreads
manages the concurrency level. To indicate in a portable manner that
the implementation is to resume control of concurrency level, call this
routine with a level argument of zero (0).
The concurrency level value can be obtained using the pthread_getcon‐
currency(3) routine.
RETURN VALUES
If an error condition occurs, this routine returns an integer value
indicating the type of error. Possible return values are as follows:
Successful completion. The value specified by level is negative. The
value specified by level would cause a system resource to be exceeded.
ERRORS
None
SEE ALSO
Functions: pthread_getconcurrency(3)
Manuals: Guide to DECthreads and Programmer's Guide
pthread_setconcurrency(3)
