Acquires a permit from this semaphore, blocking until one is available, or the thread is Java.Lang.Thread.Interrupt.

Acquires a permit, if one is available and returns immediately, reducing the number of available permits by one.

If no permit is available then the current thread becomes disabled for thread scheduling purposes and lies dormant until one of two things happens:

• Some other thread invokes the Semaphore.Release method for this semaphore and the current thread is next to be assigned a permit; or
• Some other thread Java.Lang.Thread.Interrupt the current thread.

If the current thread:

• has its interrupted status set on entry to this method; or
• is Java.Lang.Thread.Interrupt while waiting for a permit,

[Android Documentation]