Metered concurrency: Difference between revisions
→{{header|Phix}}
Line 1,144:
unit 4 acquired
unit 4 released</pre>
=={{header|Phix}}==
{{trans|Euphoria}}
Requires 0.7.6 or later
<lang Phix>sequence sems = {}
constant COUNTER = 1, QUEUE = 2
function semaphore(integer n)
if n>0 then
sems = append(sems,{n,{}})
return length(sems)
else
return 0
end if
end function
procedure acquire(integer id)
if sems[id][COUNTER]=0 then
task_suspend(task_self())
sems[id][QUEUE] &= task_self()
task_yield()
end if
sems[id][COUNTER] -= 1
end procedure
procedure release(integer id)
sems[id][COUNTER] += 1
if length(sems[id][QUEUE])>0 then
task_schedule(sems[id][QUEUE][1],1)
sems[id][QUEUE] = sems[id][QUEUE][2..$]
end if
end procedure
function count(integer id)
return sems[id][COUNTER]
end function
procedure delay(atom delaytime)
atom t = time()
while time()-t<delaytime do
task_yield()
end while
end procedure
integer sem = semaphore(4)
procedure worker()
acquire(sem)
printf(1,"- Task %d acquired semaphore.\n",task_self())
delay(2)
release(sem)
printf(1,"+ Task %d released semaphore.\n",task_self())
end procedure
for i=1 to 10 do
integer task = task_create(routine_id("worker"),{})
task_schedule(task,1)
task_yield()
end for
integer sc = 0
atom t0 = time()+1
while length(task_list())>1 do
task_yield()
integer scnew = count(sem)
if scnew!=sc
or time()>t0 then
sc = scnew
printf(1,"Semaphore count now %d\n",{sc})
t0 = time()+2
end if
end while
?"done"</lang>
{{out}}
<pre>
- Task 2 acquired semaphore.
- Task 3 acquired semaphore.
- Task 4 acquired semaphore.
- Task 5 acquired semaphore.
Semaphore count now 0
+ Task 4 released semaphore.
- Task 6 acquired semaphore.
+ Task 3 released semaphore.
- Task 7 acquired semaphore.
+ Task 2 released semaphore.
- Task 8 acquired semaphore.
+ Task 5 released semaphore.
- Task 9 acquired semaphore.
Semaphore count now 0
+ Task 9 released semaphore.
- Task 10 acquired semaphore.
+ Task 8 released semaphore.
- Task 11 acquired semaphore.
+ Task 7 released semaphore.
+ Task 6 released semaphore.
Semaphore count now 2
+ Task 11 released semaphore.
+ Task 10 released semaphore.
Semaphore count now 4
"done"
</pre>
=={{header|PicoLisp}}==
Line 1,154 ⟶ 1,255:
(prinl "Unit " U " releasing the semaphore") )
(bye) ) ) )</lang>
=={{header|PureBasic}}==
This launches a few threads in parallel, but restricted by the counter.
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