[ViewVC] Contents of: cvs/Coro/README

NAME
    Coro - coroutine process abstraction

SYNOPSIS
     use Coro;

     async {
        # some asynchronous thread of execution
     };

     # alternatively create an async process like this:

     sub some_func : Coro {
        # some more async code
     }

     cede;

DESCRIPTION
    This module collection manages coroutines. Coroutines are similar to
    threads but don't run in parallel.

    In this module, coroutines are defined as "callchain + lexical variables
    + @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
    callchain, it's own set of lexicals and it's own set of perl's most
    important global variables.

    $main
        This coroutine represents the main program.

    $current (or as function: current)
        The current coroutine (the last coroutine switched to). The initial
        value is $main (of course).

    $idle
        The coroutine to switch to when no other coroutine is running. The
        default implementation prints "FATAL: deadlock detected" and exits.

  STATIC METHODS
    Static methods are actually functions that operate on the current
    process only.

    async { ... } [@args...]
        Create a new asynchronous process and return it's process object
        (usually unused). When the sub returns the new process is
        automatically terminated.

        When the coroutine dies, the program will exit, just as in the main
        program.

           # create a new coroutine that just prints its arguments
           async {
              print "@_\n";
           } 1,2,3,4;

    schedule
        Calls the scheduler. Please note that the current process will not
        be put into the ready queue, so calling this function usually means
        you will never be called again.

    cede
        "Cede" to other processes. This function puts the current process
        into the ready queue and calls "schedule", which has the effect of
        giving up the current "timeslice" to other coroutines of the same or
        higher priority.

    terminate [arg...]
        Terminates the current process with the given status values (see
        cancel).

    # dynamic methods

  PROCESS METHODS
    These are the methods you can call on process objects.

    new Coro \&sub [, @args...]
        Create a new process and return it. When the sub returns the process
        automatically terminates as if "terminate" with the returned values
        were called. To make the process run you must first put it into the
        ready queue by calling the ready method.

    $process->ready
        Put the given process into the ready queue.

    $process->cancel (arg...)
        Terminates the given process and makes it return the given arguments
        as status (default: the empty list).

    $process->join
        Wait until the coroutine terminates and return any values given to
        the "terminate" or "cancel" functions. "join" can be called multiple
        times from multiple processes.

    $oldprio = $process->prio($newprio)
        Sets (or gets, if the argument is missing) the priority of the
        process. Higher priority processes get run before lower priority
        processes. Priorities are small signed integers (currently -4 ..
        +3), that you can refer to using PRIO_xxx constants (use the import
        tag :prio to get then):

           PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
               3    >     1     >      0      >    -1    >    -3     >    -4

           # set priority to HIGH
           current->prio(PRIO_HIGH);

        The idle coroutine ($Coro::idle) always has a lower priority than
        any existing coroutine.

        Changing the priority of the current process will take effect
        immediately, but changing the priority of processes in the ready
        queue (but not running) will only take effect after the next
        schedule (of that process). This is a bug that will be fixed in some
        future version.

    $newprio = $process->nice($change)
        Similar to "prio", but subtract the given value from the priority
        (i.e. higher values mean lower priority, just as in unix).

    $olddesc = $process->desc($newdesc)
        Sets (or gets in case the argument is missing) the description for
        this process. This is just a free-form string you can associate with
        a process.

BUGS/LIMITATIONS
     - you must make very sure that no coro is still active on global
       destruction. very bad things might happen otherwise (usually segfaults).

     - this module is not thread-safe. You should only ever use this module
       from the same thread (this requirement might be losened in the future
       to allow per-thread schedulers, but Coro::State does not yet allow
       this).

SEE ALSO
    Support/Utility: Coro::Cont, Coro::Specific, Coro::State, Coro::Util.

    Locking/IPC: Coro::Signal, Coro::Channel, Coro::Semaphore,
    Coro::SemaphoreSet, Coro::RWLock.

    Event/IO: Coro::Timer, Coro::Event, Coro::Handle, Coro::Socket,
    Coro::Select.

    Embedding: <Coro:MakeMaker>

AUTHOR
     Marc Lehmann <schmorp@schmorp.de>
     http://home.schmorp.de/

Revision:	1.3
Committed:	Mon Nov 6 19:56:26 2006 UTC (17 years, 6 months ago) by root
Branch:	MAIN
CVS Tags:	rel-2_5, stack_sharing
Changes since 1.2:	+4 -1 lines
Log Message:	* empty log message *
#	Content
1	NAME
2	Coro - coroutine process abstraction
3
4	SYNOPSIS
5	use Coro;
6
7	async {
8	# some asynchronous thread of execution
9	};
10
11	# alternatively create an async process like this:
12
13	sub some_func : Coro {
14	# some more async code
15	}
16
17	cede;
18
19	DESCRIPTION
20	This module collection manages coroutines. Coroutines are similar to
21	threads but don't run in parallel.
22
23	In this module, coroutines are defined as "callchain + lexical variables
24	+ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
25	callchain, it's own set of lexicals and it's own set of perl's most
26	important global variables.
27
28	$main
29	This coroutine represents the main program.
30
31	$current (or as function: current)
32	The current coroutine (the last coroutine switched to). The initial
33	value is $main (of course).
34
35	$idle
36	The coroutine to switch to when no other coroutine is running. The
37	default implementation prints "FATAL: deadlock detected" and exits.
38
39	STATIC METHODS
40	Static methods are actually functions that operate on the current
41	process only.
42
43	async { ... } [@args...]
44	Create a new asynchronous process and return it's process object
45	(usually unused). When the sub returns the new process is
46	automatically terminated.
47
48	When the coroutine dies, the program will exit, just as in the main
49	program.
50
51	# create a new coroutine that just prints its arguments
52	async {
53	print "@_\n";
54	} 1,2,3,4;
55
56	schedule
57	Calls the scheduler. Please note that the current process will not
58	be put into the ready queue, so calling this function usually means
59	you will never be called again.
60
61	cede
62	"Cede" to other processes. This function puts the current process
63	into the ready queue and calls "schedule", which has the effect of
64	giving up the current "timeslice" to other coroutines of the same or
65	higher priority.
66
67	terminate [arg...]
68	Terminates the current process with the given status values (see
69	cancel).
70
71	# dynamic methods
72
73	PROCESS METHODS
74	These are the methods you can call on process objects.
75
76	new Coro \&sub [, @args...]
77	Create a new process and return it. When the sub returns the process
78	automatically terminates as if "terminate" with the returned values
79	were called. To make the process run you must first put it into the
80	ready queue by calling the ready method.
81
82	$process->ready
83	Put the given process into the ready queue.
84
85	$process->cancel (arg...)
86	Terminates the given process and makes it return the given arguments
87	as status (default: the empty list).
88
89	$process->join
90	Wait until the coroutine terminates and return any values given to
91	the "terminate" or "cancel" functions. "join" can be called multiple
92	times from multiple processes.
93
94	$oldprio = $process->prio($newprio)
95	Sets (or gets, if the argument is missing) the priority of the
96	process. Higher priority processes get run before lower priority
97	processes. Priorities are small signed integers (currently -4 ..
98	+3), that you can refer to using PRIO_xxx constants (use the import
99	tag :prio to get then):
100
101	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
102	3 > 1 > 0 > -1 > -3 > -4
103
104	# set priority to HIGH
105	current->prio(PRIO_HIGH);
106
107	The idle coroutine ($Coro::idle) always has a lower priority than
108	any existing coroutine.
109
110	Changing the priority of the current process will take effect
111	immediately, but changing the priority of processes in the ready
112	queue (but not running) will only take effect after the next
113	schedule (of that process). This is a bug that will be fixed in some
114	future version.
115
116	$newprio = $process->nice($change)
117	Similar to "prio", but subtract the given value from the priority
118	(i.e. higher values mean lower priority, just as in unix).
119
120	$olddesc = $process->desc($newdesc)
121	Sets (or gets in case the argument is missing) the description for
122	this process. This is just a free-form string you can associate with
123	a process.
124
125	BUGS/LIMITATIONS
126	- you must make very sure that no coro is still active on global
127	destruction. very bad things might happen otherwise (usually segfaults).
128
129	- this module is not thread-safe. You should only ever use this module
130	from the same thread (this requirement might be losened in the future
131	to allow per-thread schedulers, but Coro::State does not yet allow
132	this).
133
134	SEE ALSO
135	Support/Utility: Coro::Cont, Coro::Specific, Coro::State, Coro::Util.
136
137	Locking/IPC: Coro::Signal, Coro::Channel, Coro::Semaphore,
138	Coro::SemaphoreSet, Coro::RWLock.
139
140	Event/IO: Coro::Timer, Coro::Event, Coro::Handle, Coro::Socket,
141	Coro::Select.
142
143	Embedding: <Coro:MakeMaker>
144
145	AUTHOR
146	Marc Lehmann <schmorp@schmorp.de>
147	http://home.schmorp.de/
148