[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.

           # 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...)
        Temrinates 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:	1.2
Committed:	Sat Aug 20 01:10:22 2005 UTC (18 years, 9 months ago) by root
Branch:	MAIN
CVS Tags:	rel-2_0, rel-2_1, rel-1_9, rel-1_2, rel-1_5, rel-1_4, rel-1_7, rel-1_6, rel-1_31
Changes since 1.1:	+9 -3 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	# create a new coroutine that just prints its arguments
49	async {
50	print "@_\n";
51	} 1,2,3,4;
52
53	schedule
54	Calls the scheduler. Please note that the current process will not
55	be put into the ready queue, so calling this function usually means
56	you will never be called again.
57
58	cede
59	"Cede" to other processes. This function puts the current process
60	into the ready queue and calls "schedule", which has the effect of
61	giving up the current "timeslice" to other coroutines of the same or
62	higher priority.
63
64	terminate [arg...]
65	Terminates the current process with the given status values (see
66	cancel).
67
68	# dynamic methods
69
70	PROCESS METHODS
71	These are the methods you can call on process objects.
72
73	new Coro \&sub [, @args...]
74	Create a new process and return it. When the sub returns the process
75	automatically terminates as if "terminate" with the returned values
76	were called. To make the process run you must first put it into the
77	ready queue by calling the ready method.
78
79	$process->ready
80	Put the given process into the ready queue.
81
82	$process->cancel (arg...)
83	Temrinates the given process and makes it return the given arguments
84	as status (default: the empty list).
85
86	$process->join
87	Wait until the coroutine terminates and return any values given to
88	the "terminate" or "cancel" functions. "join" can be called multiple
89	times from multiple processes.
90
91	$oldprio = $process->prio($newprio)
92	Sets (or gets, if the argument is missing) the priority of the
93	process. Higher priority processes get run before lower priority
94	processes. Priorities are small signed integers (currently -4 ..
95	+3), that you can refer to using PRIO_xxx constants (use the import
96	tag :prio to get then):
97
98	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
99	3 > 1 > 0 > -1 > -3 > -4
100
101	# set priority to HIGH
102	current->prio(PRIO_HIGH);
103
104	The idle coroutine ($Coro::idle) always has a lower priority than
105	any existing coroutine.
106
107	Changing the priority of the current process will take effect
108	immediately, but changing the priority of processes in the ready
109	queue (but not running) will only take effect after the next
110	schedule (of that process). This is a bug that will be fixed in some
111	future version.
112
113	$newprio = $process->nice($change)
114	Similar to "prio", but subtract the given value from the priority
115	(i.e. higher values mean lower priority, just as in unix).
116
117	$olddesc = $process->desc($newdesc)
118	Sets (or gets in case the argument is missing) the description for
119	this process. This is just a free-form string you can associate with
120	a process.
121
122	BUGS/LIMITATIONS
123	- you must make very sure that no coro is still active on global
124	destruction. very bad things might happen otherwise (usually segfaults).
125
126	- this module is not thread-safe. You should only ever use this module
127	from the same thread (this requirement might be losened in the future
128	to allow per-thread schedulers, but Coro::State does not yet allow
129	this).
130
131	SEE ALSO
132	Support/Utility: Coro::Cont, Coro::Specific, Coro::State, Coro::Util.
133
134	Locking/IPC: Coro::Signal, Coro::Channel, Coro::Semaphore,
135	Coro::SemaphoreSet, Coro::RWLock.
136
137	Event/IO: Coro::Timer, Coro::Event, Coro::Handle, Coro::Socket,
138	Coro::Select.
139
140	Embedding: <Coro:MakeMaker>
141
142	AUTHOR
143	Marc Lehmann <schmorp@schmorp.de>
144	http://home.schmorp.de/
145