THREADWAIT THREADWAIT Wait on a thread to complete execution

Usage

The threadwait function waits for the given thread to complete
execution, and stops execution of the current thread (the one calling
threadwait) until the given thread completes.  The syntax for its
use is 

   success = threadwait(handle)

where handle is the value returned by threadnew and success
is a logical vaariable that will be 1 if the wait was successful
or 0 if the wait times out.  By default, the wait is indefinite.  It
is better to use the following form of the function

   success = threadwait(handle,timeout)

where timeout is the amount of time (in milliseconds) for 
the threadwait function to wait before a timeout occurs.  
If the threadwait function succeeds, then the return 
value is a logical 1, and if it fails, the return value 
is a logical 0.  Note that you can call threadwait multiple
times on a thread, and if the thread is completed, each one
will succeed.