… | |
… | |
39 | |
39 | |
40 | my $w = EV::child 666, sub { |
40 | my $w = EV::child 666, sub { |
41 | my ($w, $revents) = @_; |
41 | my ($w, $revents) = @_; |
42 | my $status = $w->rstatus; |
42 | my $status = $w->rstatus; |
43 | }; |
43 | }; |
|
|
44 | |
|
|
45 | # STAT CHANGES |
|
|
46 | my $w = EV::stat "/etc/passwd", 10, sub { |
|
|
47 | my ($w, $revents) = @_; |
|
|
48 | warn $w->path, " has changed somehow.\n"; |
|
|
49 | }; |
44 | |
50 | |
45 | # MAINLOOP |
51 | # MAINLOOP |
46 | EV::loop; # loop until EV::unloop is called or all watchers stop |
52 | EV::loop; # loop until EV::unloop is called or all watchers stop |
47 | EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled |
53 | EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled |
48 | EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block |
54 | EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block |
49 | |
55 | |
50 | =head1 DESCRIPTION |
56 | =head1 DESCRIPTION |
51 | |
57 | |
52 | This module provides an interface to libev |
58 | This module provides an interface to libev |
53 | (L<http://software.schmorp.de/pkg/libev.html>). |
59 | (L<http://software.schmorp.de/pkg/libev.html>). While the documentation |
|
|
60 | below is comprehensive, one might also consult the documentation of libev |
|
|
61 | itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on |
|
|
62 | watcher semantics or some discussion on the available backends, or how to |
|
|
63 | force a specific backend with C<LIBEV_FLAGS>. |
54 | |
64 | |
55 | =cut |
65 | =cut |
56 | |
66 | |
57 | package EV; |
67 | package EV; |
58 | |
68 | |
59 | use strict; |
69 | use strict; |
60 | |
70 | |
61 | BEGIN { |
71 | BEGIN { |
62 | our $VERSION = '1.2'; |
72 | our $VERSION = '1.4'; |
63 | use XSLoader; |
73 | use XSLoader; |
64 | XSLoader::load "EV", $VERSION; |
74 | XSLoader::load "EV", $VERSION; |
65 | } |
75 | } |
66 | |
76 | |
67 | @EV::IO::ISA = |
77 | @EV::IO::ISA = |
… | |
… | |
69 | @EV::Periodic::ISA = |
79 | @EV::Periodic::ISA = |
70 | @EV::Signal::ISA = |
80 | @EV::Signal::ISA = |
71 | @EV::Idle::ISA = |
81 | @EV::Idle::ISA = |
72 | @EV::Prepare::ISA = |
82 | @EV::Prepare::ISA = |
73 | @EV::Check::ISA = |
83 | @EV::Check::ISA = |
|
|
84 | @EV::Child::ISA = |
|
|
85 | @EV::Embed::ISA = |
74 | @EV::Child::ISA = "EV::Watcher"; |
86 | @EV::Stat::ISA = "EV::Watcher"; |
75 | |
87 | |
76 | =head1 BASIC INTERFACE |
88 | =head1 BASIC INTERFACE |
77 | |
89 | |
78 | =over 4 |
90 | =over 4 |
79 | |
91 | |
… | |
… | |
142 | of them triggers, then they will be stopped and freed, and the callback |
154 | of them triggers, then they will be stopped and freed, and the callback |
143 | invoked. |
155 | invoked. |
144 | |
156 | |
145 | =back |
157 | =back |
146 | |
158 | |
147 | =head2 WATCHER |
159 | =head2 WATCHER OBJECTS |
148 | |
160 | |
149 | A watcher is an object that gets created to record your interest in some |
161 | A watcher is an object that gets created to record your interest in some |
150 | event. For instance, if you want to wait for STDIN to become readable, you |
162 | event. For instance, if you want to wait for STDIN to become readable, you |
151 | would create an EV::io watcher for that: |
163 | would create an EV::io watcher for that: |
152 | |
164 | |
… | |
… | |
177 | |
189 | |
178 | Also, all methods changing some aspect of a watcher (->set, ->priority, |
190 | Also, all methods changing some aspect of a watcher (->set, ->priority, |
179 | ->fh and so on) automatically stop and start it again if it is active, |
191 | ->fh and so on) automatically stop and start it again if it is active, |
180 | which means pending events get lost. |
192 | which means pending events get lost. |
181 | |
193 | |
182 | =head2 WATCHER TYPES |
194 | =head2 COMMON WATCHER METHODS |
183 | |
195 | |
184 | Now lets move to the existing watcher types and asociated methods. |
196 | This section lists methods common to all watchers. |
185 | |
|
|
186 | The following methods are available for all watchers. Then followes a |
|
|
187 | description of each watcher constructor (EV::io, EV::timer, EV::periodic, |
|
|
188 | EV::signal, EV::child, EV::idle, EV::prepare and EV::check), followed by |
|
|
189 | any type-specific methods (if any). |
|
|
190 | |
197 | |
191 | =over 4 |
198 | =over 4 |
192 | |
199 | |
193 | =item $w->start |
200 | =item $w->start |
194 | |
201 | |
… | |
… | |
233 | watchers with higher priority will be invoked first. The valid range of |
240 | watchers with higher priority will be invoked first. The valid range of |
234 | priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default |
241 | priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default |
235 | -2). If the priority is outside this range it will automatically be |
242 | -2). If the priority is outside this range it will automatically be |
236 | normalised to the nearest valid priority. |
243 | normalised to the nearest valid priority. |
237 | |
244 | |
238 | The default priority of any newly-created weatcher is 0. |
245 | The default priority of any newly-created watcher is 0. |
|
|
246 | |
|
|
247 | Note that the priority semantics have not yet been fleshed out and are |
|
|
248 | subject to almost certain change. |
239 | |
249 | |
240 | =item $w->trigger ($revents) |
250 | =item $w->trigger ($revents) |
241 | |
251 | |
242 | Call the callback *now* with the given event mask. |
252 | Call the callback *now* with the given event mask. |
243 | |
253 | |
|
|
254 | =item $previous_state = $w->keepalive ($bool) |
|
|
255 | |
|
|
256 | Normally, C<EV::loop> will return when there are no active watchers |
|
|
257 | (which is a "deadlock" because no progress can be made anymore). This is |
|
|
258 | convinient because it allows you to start your watchers (and your jobs), |
|
|
259 | call C<EV::loop> once and when it returns you know that all your jobs are |
|
|
260 | finished (or they forgot to register some watchers for their task :). |
|
|
261 | |
|
|
262 | Sometimes, however, this gets in your way, for example when you the module |
|
|
263 | that calls C<EV::loop> (usually the main program) is not the same module |
|
|
264 | as a long-living watcher (for example a DNS client module written by |
|
|
265 | somebody else even). Then you might want any outstanding requests to be |
|
|
266 | handled, but you would not want to keep C<EV::loop> from returning just |
|
|
267 | because you happen to have this long-running UDP port watcher. |
|
|
268 | |
|
|
269 | In this case you can clear the keepalive status, which means that even |
|
|
270 | though your watcher is active, it won't keep C<EV::loop> from returning. |
|
|
271 | |
|
|
272 | The initial value for keepalive is true (enabled), and you cna change it |
|
|
273 | any time. |
|
|
274 | |
|
|
275 | Example: Register an IO watcher for some UDP socket but do not keep the |
|
|
276 | event loop from running just because of that watcher. |
|
|
277 | |
|
|
278 | my $udp_socket = ... |
|
|
279 | my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; |
|
|
280 | $udp_watcher->keepalive (0); |
|
|
281 | |
|
|
282 | =back |
|
|
283 | |
|
|
284 | |
|
|
285 | =head2 WATCHER TYPES |
|
|
286 | |
|
|
287 | Each of the following subsections describes a single watcher type. |
|
|
288 | |
|
|
289 | =head3 IO WATCHERS - is this file descriptor readable or writable? |
|
|
290 | |
|
|
291 | =over 4 |
244 | |
292 | |
245 | =item $w = EV::io $fileno_or_fh, $eventmask, $callback |
293 | =item $w = EV::io $fileno_or_fh, $eventmask, $callback |
246 | |
294 | |
247 | =item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback |
295 | =item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback |
248 | |
296 | |
249 | As long as the returned watcher object is alive, call the C<$callback> |
297 | As long as the returned watcher object is alive, call the C<$callback> |
250 | when the events specified in C<$eventmask>. |
298 | when at least one of events specified in C<$eventmask> occurs. |
251 | |
299 | |
252 | The $eventmask can be one or more of these constants ORed together: |
300 | The $eventmask can be one or more of these constants ORed together: |
253 | |
301 | |
254 | EV::READ wait until read() wouldn't block anymore |
302 | EV::READ wait until read() wouldn't block anymore |
255 | EV::WRITE wait until write() wouldn't block anymore |
303 | EV::WRITE wait until write() wouldn't block anymore |
… | |
… | |
271 | |
319 | |
272 | =item $old_eventmask = $w->events ($new_eventmask) |
320 | =item $old_eventmask = $w->events ($new_eventmask) |
273 | |
321 | |
274 | Returns the previously set event mask and optionally set a new one. |
322 | Returns the previously set event mask and optionally set a new one. |
275 | |
323 | |
|
|
324 | =back |
|
|
325 | |
|
|
326 | |
|
|
327 | =head3 TIMER WATCHERS - relative and optionally repeating timeouts |
|
|
328 | |
|
|
329 | =over 4 |
276 | |
330 | |
277 | =item $w = EV::timer $after, $repeat, $callback |
331 | =item $w = EV::timer $after, $repeat, $callback |
278 | |
332 | |
279 | =item $w = EV::timer_ns $after, $repeat, $callback |
333 | =item $w = EV::timer_ns $after, $repeat, $callback |
280 | |
334 | |
281 | Calls the callback after C<$after> seconds. If C<$repeat> is non-zero, |
335 | Calls the callback after C<$after> seconds (which may be fractional). If |
282 | the timer will be restarted (with the $repeat value as $after) after the |
336 | C<$repeat> is non-zero, the timer will be restarted (with the $repeat |
283 | callback returns. |
337 | value as $after) after the callback returns. |
284 | |
338 | |
285 | This means that the callback would be called roughly after C<$after> |
339 | This means that the callback would be called roughly after C<$after> |
286 | seconds, and then every C<$repeat> seconds. The timer does his best not |
340 | seconds, and then every C<$repeat> seconds. The timer does his best not |
287 | to drift, but it will not invoke the timer more often then once per event |
341 | to drift, but it will not invoke the timer more often then once per event |
288 | loop iteration, and might drift in other cases. If that isn't acceptable, |
342 | loop iteration, and might drift in other cases. If that isn't acceptable, |
… | |
… | |
294 | |
348 | |
295 | The C<timer_ns> variant doesn't start (activate) the newly created watcher. |
349 | The C<timer_ns> variant doesn't start (activate) the newly created watcher. |
296 | |
350 | |
297 | =item $w->set ($after, $repeat) |
351 | =item $w->set ($after, $repeat) |
298 | |
352 | |
299 | Reconfigures the watcher, see the constructor above for details. Can be at |
353 | Reconfigures the watcher, see the constructor above for details. Can be called at |
300 | any time. |
354 | any time. |
301 | |
355 | |
302 | =item $w->again |
356 | =item $w->again |
303 | |
357 | |
304 | Similar to the C<start> method, but has special semantics for repeating timers: |
358 | Similar to the C<start> method, but has special semantics for repeating timers: |
… | |
… | |
315 | This behaviour is useful when you have a timeout for some IO |
369 | This behaviour is useful when you have a timeout for some IO |
316 | operation. You create a timer object with the same value for C<$after> and |
370 | operation. You create a timer object with the same value for C<$after> and |
317 | C<$repeat>, and then, in the read/write watcher, run the C<again> method |
371 | C<$repeat>, and then, in the read/write watcher, run the C<again> method |
318 | on the timeout. |
372 | on the timeout. |
319 | |
373 | |
|
|
374 | =back |
|
|
375 | |
|
|
376 | |
|
|
377 | =head3 PERIODIC WATCHERS - to cron or not to cron? |
|
|
378 | |
|
|
379 | =over 4 |
320 | |
380 | |
321 | =item $w = EV::periodic $at, $interval, $reschedule_cb, $callback |
381 | =item $w = EV::periodic $at, $interval, $reschedule_cb, $callback |
322 | |
382 | |
323 | =item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback |
383 | =item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback |
324 | |
384 | |
… | |
… | |
396 | |
456 | |
397 | The C<periodic_ns> variant doesn't start (activate) the newly created watcher. |
457 | The C<periodic_ns> variant doesn't start (activate) the newly created watcher. |
398 | |
458 | |
399 | =item $w->set ($at, $interval, $reschedule_cb) |
459 | =item $w->set ($at, $interval, $reschedule_cb) |
400 | |
460 | |
401 | Reconfigures the watcher, see the constructor above for details. Can be at |
461 | Reconfigures the watcher, see the constructor above for details. Can be called at |
402 | any time. |
462 | any time. |
403 | |
463 | |
404 | =item $w->again |
464 | =item $w->again |
405 | |
465 | |
406 | Simply stops and starts the watcher again. |
466 | Simply stops and starts the watcher again. |
407 | |
467 | |
|
|
468 | =back |
|
|
469 | |
|
|
470 | |
|
|
471 | =head3 SIGNAL WATCHERS - signal me when a signal gets signalled! |
|
|
472 | |
|
|
473 | =over 4 |
408 | |
474 | |
409 | =item $w = EV::signal $signal, $callback |
475 | =item $w = EV::signal $signal, $callback |
410 | |
476 | |
411 | =item $w = EV::signal_ns $signal, $callback |
477 | =item $w = EV::signal_ns $signal, $callback |
412 | |
478 | |
413 | Call the callback when $signal is received (the signal can be specified |
479 | Call the callback when $signal is received (the signal can be specified by |
414 | by number or by name, just as with kill or %SIG). |
480 | number or by name, just as with C<kill> or C<%SIG>). |
415 | |
481 | |
416 | EV will grab the signal for the process (the kernel only allows one |
482 | EV will grab the signal for the process (the kernel only allows one |
417 | component to receive a signal at a time) when you start a signal watcher, |
483 | component to receive a signal at a time) when you start a signal watcher, |
418 | and removes it again when you stop it. Perl does the same when you |
484 | and removes it again when you stop it. Perl does the same when you |
419 | add/remove callbacks to %SIG, so watch out. |
485 | add/remove callbacks to C<%SIG>, so watch out. |
420 | |
486 | |
421 | You can have as many signal watchers per signal as you want. |
487 | You can have as many signal watchers per signal as you want. |
422 | |
488 | |
423 | The C<signal_ns> variant doesn't start (activate) the newly created watcher. |
489 | The C<signal_ns> variant doesn't start (activate) the newly created watcher. |
424 | |
490 | |
425 | =item $w->set ($signal) |
491 | =item $w->set ($signal) |
426 | |
492 | |
427 | Reconfigures the watcher, see the constructor above for details. Can be at |
493 | Reconfigures the watcher, see the constructor above for details. Can be |
428 | any time. |
494 | called at any time. |
429 | |
495 | |
430 | =item $current_signum = $w->signal |
496 | =item $current_signum = $w->signal |
431 | |
497 | |
432 | =item $old_signum = $w->signal ($new_signal) |
498 | =item $old_signum = $w->signal ($new_signal) |
433 | |
499 | |
434 | Returns the previously set signal (always as a number not name) and |
500 | Returns the previously set signal (always as a number not name) and |
435 | optionally set a new one. |
501 | optionally set a new one. |
436 | |
502 | |
|
|
503 | =back |
|
|
504 | |
|
|
505 | |
|
|
506 | =head3 CHILD WATCHERS - watch out for process status changes |
|
|
507 | |
|
|
508 | =over 4 |
437 | |
509 | |
438 | =item $w = EV::child $pid, $callback |
510 | =item $w = EV::child $pid, $callback |
439 | |
511 | |
440 | =item $w = EV::child_ns $pid, $callback |
512 | =item $w = EV::child_ns $pid, $callback |
441 | |
513 | |
442 | Call the callback when a status change for pid C<$pid> (or any pid |
514 | Call the callback when a status change for pid C<$pid> (or any pid if |
443 | if C<$pid> is 0) has been received. More precisely: when the process |
515 | C<$pid> is 0) has been received. More precisely: when the process receives |
444 | receives a SIGCHLD, EV will fetch the outstanding exit/wait status for all |
516 | a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all |
445 | changed/zombie children and call the callback. |
517 | changed/zombie children and call the callback. |
446 | |
518 | |
447 | You can access both status and pid by using the C<rstatus> and C<rpid> |
519 | It is valid (and fully supported) to install a child watcher after a child |
448 | methods on the watcher object. |
520 | has exited but before the event loop has started its next iteration (for |
|
|
521 | example, first you C<fork>, then the new child process might exit, and |
|
|
522 | only then do you install a child watcher in the parent for the new pid). |
449 | |
523 | |
|
|
524 | You can access both exit (or tracing) status and pid by using the |
|
|
525 | C<rstatus> and C<rpid> methods on the watcher object. |
|
|
526 | |
450 | You can have as many pid watchers per pid as you want. |
527 | You can have as many pid watchers per pid as you want, they will all be |
|
|
528 | called. |
451 | |
529 | |
452 | The C<child_ns> variant doesn't start (activate) the newly created watcher. |
530 | The C<child_ns> variant doesn't start (activate) the newly created watcher. |
453 | |
531 | |
454 | =item $w->set ($pid) |
532 | =item $w->set ($pid) |
455 | |
533 | |
456 | Reconfigures the watcher, see the constructor above for details. Can be at |
534 | Reconfigures the watcher, see the constructor above for details. Can be called at |
457 | any time. |
535 | any time. |
458 | |
536 | |
459 | =item $current_pid = $w->pid |
537 | =item $current_pid = $w->pid |
460 | |
538 | |
461 | =item $old_pid = $w->pid ($new_pid) |
539 | =item $old_pid = $w->pid ($new_pid) |
… | |
… | |
470 | =item $pid = $w->rpid |
548 | =item $pid = $w->rpid |
471 | |
549 | |
472 | Return the pid of the awaited child (useful when you have installed a |
550 | Return the pid of the awaited child (useful when you have installed a |
473 | watcher for all pids). |
551 | watcher for all pids). |
474 | |
552 | |
|
|
553 | =back |
|
|
554 | |
|
|
555 | |
|
|
556 | =head3 IDLE WATCHERS - when you've got nothing better to do... |
|
|
557 | |
|
|
558 | =over 4 |
475 | |
559 | |
476 | =item $w = EV::idle $callback |
560 | =item $w = EV::idle $callback |
477 | |
561 | |
478 | =item $w = EV::idle_ns $callback |
562 | =item $w = EV::idle_ns $callback |
479 | |
563 | |
… | |
… | |
483 | The process will not block as long as any idle watchers are active, and |
567 | The process will not block as long as any idle watchers are active, and |
484 | they will be called repeatedly until stopped. |
568 | they will be called repeatedly until stopped. |
485 | |
569 | |
486 | The C<idle_ns> variant doesn't start (activate) the newly created watcher. |
570 | The C<idle_ns> variant doesn't start (activate) the newly created watcher. |
487 | |
571 | |
|
|
572 | =back |
|
|
573 | |
|
|
574 | |
|
|
575 | =head3 PREPARE WATCHERS - customise your event loop! |
|
|
576 | |
|
|
577 | =over 4 |
488 | |
578 | |
489 | =item $w = EV::prepare $callback |
579 | =item $w = EV::prepare $callback |
490 | |
580 | |
491 | =item $w = EV::prepare_ns $callback |
581 | =item $w = EV::prepare_ns $callback |
492 | |
582 | |
… | |
… | |
495 | |
585 | |
496 | See the EV::check watcher, below, for explanations and an example. |
586 | See the EV::check watcher, below, for explanations and an example. |
497 | |
587 | |
498 | The C<prepare_ns> variant doesn't start (activate) the newly created watcher. |
588 | The C<prepare_ns> variant doesn't start (activate) the newly created watcher. |
499 | |
589 | |
|
|
590 | =back |
|
|
591 | |
|
|
592 | |
|
|
593 | =head3 CHECK WATCHERS - customise your event loop even more! |
|
|
594 | |
|
|
595 | =over 4 |
500 | |
596 | |
501 | =item $w = EV::check $callback |
597 | =item $w = EV::check $callback |
502 | |
598 | |
503 | =item $w = EV::check_ns $callback |
599 | =item $w = EV::check_ns $callback |
504 | |
600 | |
… | |
… | |
549 | first). |
645 | first). |
550 | |
646 | |
551 | The C<check_ns> variant doesn't start (activate) the newly created watcher. |
647 | The C<check_ns> variant doesn't start (activate) the newly created watcher. |
552 | |
648 | |
553 | =back |
649 | =back |
|
|
650 | |
|
|
651 | =head3 STAT WATCHERS - did the file attributes just change? |
|
|
652 | |
|
|
653 | =over 4 |
|
|
654 | |
|
|
655 | =item $w = EV::stat $path, $interval, $callback |
|
|
656 | |
|
|
657 | =item $w = EV::stat_ns $path, $interval, $callback |
|
|
658 | |
|
|
659 | Call the callback when a file status change has been detected on |
|
|
660 | C<$path>. The C<$path> does not need to exist, changing from "path exists" |
|
|
661 | to "path does not exist" is a status change like any other. |
|
|
662 | |
|
|
663 | The C<$interval> is a recommended polling interval for systems where |
|
|
664 | OS-supported change notifications don't exist or are not supported. If |
|
|
665 | you use C<0> then an unspecified default is used (which is highly |
|
|
666 | recommended!), which is to be expected to be around five seconds usually. |
|
|
667 | |
|
|
668 | This watcher type is not meant for massive numbers of stat watchers, |
|
|
669 | as even with OS-supported change notifications, this can be |
|
|
670 | resource-intensive. |
|
|
671 | |
|
|
672 | The C<stat_ns> variant doesn't start (activate) the newly created watcher. |
|
|
673 | |
|
|
674 | =item $w->set ($path, $interval) |
|
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675 | |
|
|
676 | Reconfigures the watcher, see the constructor above for details. Can be |
|
|
677 | called at any time. |
|
|
678 | |
|
|
679 | =item $current_path = $w->path |
|
|
680 | |
|
|
681 | =item $old_path = $w->path ($new_path) |
|
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682 | |
|
|
683 | Returns the previously set path and optionally set a new one. |
|
|
684 | |
|
|
685 | =item $current_interval = $w->interval |
|
|
686 | |
|
|
687 | =item $old_interval = $w->interval ($new_interval) |
|
|
688 | |
|
|
689 | Returns the previously set interval and optionally set a new one. Can be |
|
|
690 | used to query the actual interval used. |
|
|
691 | |
|
|
692 | =back |
|
|
693 | |
554 | |
694 | |
555 | =head1 THREADS |
695 | =head1 THREADS |
556 | |
696 | |
557 | Threads are not supported by this module in any way. Perl pseudo-threads |
697 | Threads are not supported by this module in any way. Perl pseudo-threads |
558 | is evil stuff and must die. As soon as Perl gains real threads I will work |
698 | is evil stuff and must die. As soon as Perl gains real threads I will work |
… | |
… | |
586 | |
726 | |
587 | 1; |
727 | 1; |
588 | |
728 | |
589 | =head1 SEE ALSO |
729 | =head1 SEE ALSO |
590 | |
730 | |
591 | L<EV::DNS>. |
731 | L<EV::DNS>. |
592 | |
732 | |
593 | =head1 AUTHOR |
733 | =head1 AUTHOR |
594 | |
734 | |
595 | Marc Lehmann <schmorp@schmorp.de> |
735 | Marc Lehmann <schmorp@schmorp.de> |
596 | http://home.schmorp.de/ |
736 | http://home.schmorp.de/ |