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NAME |
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Coro - coroutine process abstraction |
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|
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SYNOPSIS |
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use Coro; |
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|
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async { |
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# some asynchronous thread of execution |
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}; |
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|
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# alternatively create an async process like this: |
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|
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sub some_func : Coro { |
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# some more async code |
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} |
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|
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cede; |
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|
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DESCRIPTION |
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This module collection manages coroutines. Coroutines are similar to |
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threads but don't run in parallel. |
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|
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In this module, coroutines are defined as "callchain + lexical variables |
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+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own |
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callchain, it's own set of lexicals and it's own set of perl's most |
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important global variables. |
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|
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$main |
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This coroutine represents the main program. |
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|
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$current (or as function: current) |
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The current coroutine (the last coroutine switched to). The initial |
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value is $main (of course). |
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|
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$idle |
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The coroutine to switch to when no other coroutine is running. The |
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default implementation prints "FATAL: deadlock detected" and exits. |
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|
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STATIC METHODS |
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Static methods are actually functions that operate on the current |
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process only. |
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|
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async { ... } [@args...] |
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Create a new asynchronous process and return it's process object |
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(usually unused). When the sub returns the new process is |
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automatically terminated. |
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|
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# create a new coroutine that just prints its arguments |
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async { |
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print "@_\n"; |
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} 1,2,3,4; |
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|
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schedule |
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Calls the scheduler. Please note that the current process will not |
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be put into the ready queue, so calling this function usually means |
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you will never be called again. |
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|
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cede |
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"Cede" to other processes. This function puts the current process |
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into the ready queue and calls "schedule", which has the effect of |
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giving up the current "timeslice" to other coroutines of the same or |
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higher priority. |
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|
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terminate [arg...] |
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Terminates the current process with the given status values (see |
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cancel). |
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|
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# dynamic methods |
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|
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PROCESS METHODS |
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These are the methods you can call on process objects. |
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|
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new Coro \&sub [, @args...] |
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Create a new process and return it. When the sub returns the process |
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automatically terminates as if "terminate" with the returned values |
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were called. To make the process run you must first put it into the |
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ready queue by calling the ready method. |
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|
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$process->ready |
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Put the given process into the ready queue. |
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|
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$process->cancel (arg...) |
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Temrinates the given process and makes it return the given arguments |
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as status (default: the empty list). |
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|
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$process->join |
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Wait until the coroutine terminates and return any values given to |
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the "terminate" or "cancel" functions. "join" can be called multiple |
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times from multiple processes. |
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|
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$oldprio = $process->prio($newprio) |
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Sets (or gets, if the argument is missing) the priority of the |
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process. Higher priority processes get run before lower priority |
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processes. Priorities are small signed integers (currently -4 .. |
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+3), that you can refer to using PRIO_xxx constants (use the import |
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tag :prio to get then): |
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|
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PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN |
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3 > 1 > 0 > -1 > -3 > -4 |
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|
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# set priority to HIGH |
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current->prio(PRIO_HIGH); |
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|
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The idle coroutine ($Coro::idle) always has a lower priority than |
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any existing coroutine. |
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|
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Changing the priority of the current process will take effect |
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immediately, but changing the priority of processes in the ready |
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queue (but not running) will only take effect after the next |
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schedule (of that process). This is a bug that will be fixed in some |
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future version. |
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|
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$newprio = $process->nice($change) |
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Similar to "prio", but subtract the given value from the priority |
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(i.e. higher values mean lower priority, just as in unix). |
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|
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$olddesc = $process->desc($newdesc) |
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Sets (or gets in case the argument is missing) the description for |
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this process. This is just a free-form string you can associate with |
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a process. |
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|
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BUGS/LIMITATIONS |
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- you must make very sure that no coro is still active on global |
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destruction. very bad things might happen otherwise (usually segfaults). |
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|
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- this module is not thread-safe. You should only ever use this module |
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from the same thread (this requirement might be losened in the future |
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to allow per-thread schedulers, but Coro::State does not yet allow |
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this). |
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|
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SEE ALSO |
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Support/Utility: Coro::Cont, Coro::Specific, Coro::State, Coro::Util. |
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|
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Locking/IPC: Coro::Signal, Coro::Channel, Coro::Semaphore, |
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Coro::SemaphoreSet, Coro::RWLock. |
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|
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Event/IO: Coro::Timer, Coro::Event, Coro::Handle, Coro::Socket, |
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Coro::Select. |
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|
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Embedding: <Coro:MakeMaker> |
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|
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AUTHOR |
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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