pthread_setconcurrency(3) Library Functions Manual pthread_setconcurrency(3)
NAME
pthread_setconcurrency - Changes the value of the concurrency level global variable for this process.
LIBRARY
DECthreads POSIX 1003.1c Library (libpthread.so)
SYNOPSIS
#include <pthread.h>
int pthread_setconcurrency(
int level);
STANDARDS
Interfaces documented on this reference page conform to industry standards 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 multithreaded 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_getconcurrency(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_getconcurrency(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 new_level is negative. The value specified by new_level would cause a system resource to be
exceeded.
ERRORS
None
RELATED INFORMATION
Functions: pthread_getconcurrency(3)
Manuals: Guide to DECthreads and Programmer's Guide delim off
pthread_setconcurrency(3)