[#BloombergLP-bslmt-Latch-countDown] = xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bslmt.adoc[bslmt]::xref:BloombergLP/bslmt/Latch.adoc[Latch]::countDown :relfileprefix: ../../../ :mrdocs: Decrement the number of events that this latch is waiting for by the specified `numEvents`, and if the resulting number of events is 0 release any waiting threads. The behavior is undefined unless `numEvents > 0` and the sum of all events that have arrived at this latch does not exceed the count with which it was initialized. Note that the initial count of events is supplied at construction. == Synopsis Declared in `<bslmt_latch.h>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- void countDown(int numEvents); ---- [.small]#Created with https://www.mrdocs.com[MrDocs]#