F.54 ctThrdBlockWait

---

Wait for a block to clear.

Short Name

ctThrdBlockWait

TYPE

Threading function

DECLARATION

NINT ctThrdBlockWait(pctBLOCK block, LONG timeout)

DESCRIPTION

ctThrdBlockWait behaves similarly to ctThrdBlockGet except that it does not acquire the block. Rather, it simply waits until the block is not acquired by any thread before permitting the thread to continue. Any number of threads can attempt to wait on a block. Whether or not all waiting threads will successfully pass the block before another thread acquires the block is system dependent. To encourage this behavior, each thread successfully passing a block automatically yields to the other threads.

RETURN

Value	Symbolic Constant	Explanation
0	NO_ERROR	Successfully acquired block.
156	NTIM_ERR	block in use by another thread. Timeout error.
636	TSYF_ERR	block get failed.

See Appendix A "c-tree Plus Error Codes" of the c-tree Plus Programmer's Reference Guide for a complete listing of valid c-tree Plus error values.

LIMITATIONS

Can only be used with a ctThrd library.

SEE ALSO

ctThrdBlockCls, ctThrdBlockGet, and ctThrdBlockRel.