[#BloombergLP-bslmt-SemaphoreImpl-06]
= xref:BloombergLP.adoc[BloombergLP]::xref:BloombergLP/bslmt.adoc[bslmt]::xref:BloombergLP/bslmt/SemaphoreImpl-0a.adoc[SemaphoreImpl]<xref:BloombergLP/bslmt/Platform/PosixSemaphore.adoc[Platform::PosixSemaphore]>
:relfileprefix: ../../
:mrdocs:

This class provides a full specialization of `SemaphoreImpl` for pthreads. The implementation provided here defines an efficient proxy for the `sem_t` pthread type, and related operations.

== Synopsis

Declared in `<bslmt_semaphoreimpl_pthread.h>`

[source,cpp,subs="verbatim,replacements,macros,-callouts"]
----
template<>
class xref:BloombergLP/bslmt/SemaphoreImpl-0a.adoc[SemaphoreImpl]<xref:BloombergLP/bslmt/Platform/PosixSemaphore.adoc[Platform::PosixSemaphore]>;
----

== Member Functions

[cols="1,4"]
|===
| Name| Description
| xref:BloombergLP/bslmt/SemaphoreImpl-06/2constructor.adoc[`SemaphoreImpl`]         [.small]#[constructor]#
| Create a semaphore initialized to the specified `count`. This method does not return normally unless there are sufficient system resources to construct the object.
| xref:BloombergLP/bslmt/SemaphoreImpl-06/2destructor.adoc[`~SemaphoreImpl`] [.small]#[destructor]#
| Destroy a semaphore
| xref:BloombergLP/bslmt/SemaphoreImpl-06/getValue.adoc[`getValue`] 
| Return the current value of this semaphore.
| xref:BloombergLP/bslmt/SemaphoreImpl-06/post-00.adoc[`post`] 
| `post` overloads
| xref:BloombergLP/bslmt/SemaphoreImpl-06/tryWait.adoc[`tryWait`] 
| Decrement the count of this semaphore if it is positive and return 0. Return a non‐zero value otherwise.
| xref:BloombergLP/bslmt/SemaphoreImpl-06/wait.adoc[`wait`] 
| Block until the count of this semaphore is a positive value and atomically decrement it.
|===



[.small]#Created with https://www.mrdocs.com[MrDocs]#