pthread_setconcurrency(3C) is provided for standards compliance. pthread_setconcurrency() is used by an application to inform the system of the application's desired concurrency level. For the threads implementation introduced in the Solaris 9 release, this interface has no effect, all runnable threads are attached to LWPs.
#include <pthread.h> int pthread_setconcurrency(int new_level);
The value specified by new_level is negative.
The value specified by new_level would cause a system resource to be exceeded.