thrd_success, thrd_timedout, thrd_busy, thrd_nomem, thrd_error

Defined in header <threads.h> 
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_success indicates successful return value
thrd_nomem indicates unsuccessful return value due to out of memory condition
thrd_timedout indicates timed out return value
thrd_busy indicates unsuccessful return value due to resource temporary unavailable
thrd_error indicates unsuccessful return value

References

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