cc –mt [ flag... ] file...[ library... ] #include <thread.h> int thr_setconcurrency(int new_level);
These functions are obsolete and maintained for compatibility only. The thr_setconcurrency() function updates the desired concurrency level that libthread maintains for the calling process. This value does not affect the behavior of the calling process.
The thr_getconcurrency() function returns the current value for the desired concurrency level.
The thr_getconcurrency() function always returns the current value for the desired concurrency level.
If successful, the thr_setconcurrency() function returns 0. Otherwise, a non-zero value is returned to indicate the error.
The thr_setconcurrency() function will fail if:
The specified concurrency level would cause a system resource to be exceeded.
The value for new_level is negative.
See attributes(5) for descriptions of the following attributes: