From cppreference.com
enum{thrd_success=/* unspecified */,thrd_nomem=/* unspecified */,thrd_timedout=/* unspecified */,thrd_busy=/* unspecified */,thrd_error=/* unspecified */};(since C11)Identifiers for thread states and errors.
Constant Explanation thrd_successindicates successful return value thrd_nomemindicates unsuccessful return value due to out of memory condition thrd_timedoutindicates timed out return value thrd_busyindicates unsuccessful return value due to resource temporary unavailable thrd_errorindicates unsuccessful return value References
C17 standard (ISO/IEC 9899:2018):
7.26.1/5 thrd_success, thrd_timedout, ... (p: 275)
C11 standard (ISO/IEC 9899:2011):
7.26.1/5 thrd_success, thrd_timedout, ... (p: 377)