stop executing loop after a selected time

Question

I wanna stop executing loop after a selected time. Means when looping it will try to execute an argument and take a long time then it will finish working and go to next argument. such as :

for ($i=2 ; $i <= 100 ; $i++)

Here, suppose it will loop 3,4,5,6,7,8,9,10 and in 11 it will take a long time to execute. So i just wanna stop it after ( i.e 10 seconds ) and take next option i mean 12,13,14... etc. So, how can i do this. I set up this set_time_limit(10); , but it is not working here.

related to http://stackoverflow.com/q/10587323/1689451 – Rudolf Mühlbauer Nov 02 '12 at 12:46 — Rudolf Mühlbauer, Nov 02 '12 at 12:46

score 3 · Answer 1 · answered Nov 02 '12 at 12:52

3

You can use microtime() to measure time elapsed. Note that this will only break after an iteration has completed.

$start = microtime(true);
$limit = 10;  // Seconds

for ($i=2 ; $i <= 100 ; $i++) {
  if (microtime(true) - $start >= $limit) {
    break;
  }
}

answered Nov 02 '12 at 12:52

Markus Hedlund

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it will check at start of iteration but probably he want a solution to break the loop during the iteration. – Mansoor Jafar Nov 02 '12 at 12:54
may be it will break my whole script if i put it globally ? @mansoor , ya right . – Imran Abdur Rahim Nov 02 '12 at 13:01
@mansoor That's what I meant with "Note that this will only break after an iteration has completed". Can't come up with a scenario where this is *not* what you want – Markus Hedlund Nov 02 '12 at 17:15

GolezTrol · Answer 2 · 2012-11-02T12:50:58.297

0

That is quite complex. You will have to create a separate thread to do the processing in, so your main thread can check if it has been running for too long.

Those threads are called 'forks' in PHP.

You'll have to investigate the Process Control functions and especially [pcntl_fork][2]. Then, using pcntl_sigtimedwait, you can wait for the forked process during a given timeout. When pcntl_sigtimedwait returns, you can check its returned value to see if the process timed out.

edited Nov 02 '12 at 12:50

answered Nov 02 '12 at 12:45

GolezTrol

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Yes. 'Thread' may not be the right term. However, as I showed, there are ways to fork the process and run the forked child process in parallel with the (waiting) main process. – GolezTrol Nov 02 '12 at 13:07
probably here `OS forks` can be used. – Mansoor Jafar Nov 02 '12 at 13:08
Yes, that's what those PHP functions use in the background. – GolezTrol Nov 02 '12 at 13:09

stop executing loop after a selected time

2 Answers2