The Wait command pauses the current thread until the threads specified as arguments finish.

$\mathrm{with}\left(\mathrm{Threads}\right)$

$\left[\mathrm{Add}\,\mathrm{ConditionVariable}\,\mathrm{Create}\,\mathrm{Map}\,\mathrm{Mul}\,\mathrm{Mutex}\,\mathrm{Self}\,\mathrm{Seq}\,\mathrm{Sleep}\,\mathrm{Task}\,\mathrm{Wait}\right]$

p := proc( limit )
   local now, start;
   start := time[real]();
   now := start;
   
   while now - start < limit        
   do
       Threads:-Sleep( 0.1 );
       now := time[real]();
   end;

   return now-start;
end:

$\mathrm{id}≔\mathrm{Create}\left(p\left(1\right)\&comma;'\mathrm{out}'\right)\&colon;$

$\mathrm{Wait}\left(\mathrm{id}\right)\&colon;$

$\mathrm{out}$

$1.003$

$\mathrm{id1}≔\mathrm{Create}\left(p\left(1\right)\&comma;'\mathrm{out1}'\right)\&colon;$

$\mathrm{id2}≔\mathrm{Create}\left(p\left(2\right)\&comma;'\mathrm{out2}'\right)\&colon;$

$\mathrm{Wait}\left(\mathrm{id1}\&comma;\mathrm{id2}\right)\&colon;$

$\mathrm{out1}$

$1.002$

$\mathrm{out2}$

$2.015$