NAME

thrd_equal — compare thread IDs

SYNOPSIS

#include <threads.h>

int thrd_equal(thrd_t thr0, thrd_t thr1);


DESCRIPTION

^[CX] The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here and the ISO C standard is unintentional. This volume of POSIX.1-2024 defers to the ISO C standard.

The thrd_equal() function shall determine whether the thread identified by thr0 refers to the thread identified by thr1.

^[CX] The thrd_equal() function shall not be affected if the calling thread executes a signal handler during the call.

RETURN VALUE

The thrd_equal() function shall return a non-zero value if thr0 and thr1 are equal; otherwise, zero shall be returned.

If either thr0 or thr1 is not a valid thread ID ^[CX]  and is not equal to PTHREAD_NULL (which is defined in <pthread.h>),  the behavior is undefined.

ERRORS

No errors are defined.

EXAMPLES

None.

APPLICATION USAGE

None.

RATIONALE

See the RATIONALE section for pthread_equal.

The thrd_equal() function is not affected by signal handlers for the reasons stated in XRAT B.2.3 Error Numbers.

FUTURE DIRECTIONS

None.

SEE ALSO

pthread_equal, thrd_current

XBD <pthread.h>, <threads.h>

CHANGE HISTORY

First released in Issue 8. Included for alignment with the ISO/IEC 9899:2018 standard.