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1package threads;
2
73e09c8f 3use 5.007_003;
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4use strict;
5use warnings;
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6use Config;
7
8BEGIN {
9 unless ($Config{useithreads}) {
10 my @caller = caller(2);
11 die <<EOF;
12$caller[1] line $caller[2]:
13
14This Perl hasn't been configured and built properly for the threads
15module to work. (The 'useithreads' configuration option hasn't been used.)
16
17Having threads support requires all of Perl and all of the modules in
18the Perl installation to be rebuilt, it is not just a question of adding
19the threads module. (In other words, threaded and non-threaded Perls
20are binary incompatible.)
21
22If you want to the use the threads module, please contact the people
23who built your Perl.
24
25Cannot continue, aborting.
26EOF
27 }
28}
47ba8780 29
68795e93 30use overload
43d3ddbe 31 '==' => \&equal,
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32 'fallback' => 1;
33
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34#use threads::Shared;
35
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36BEGIN {
37 warn "Warning, threads::shared has already been loaded. ".
38 "To enable shared variables for these modules 'use threads' ".
39 "must be called before any of those modules are loaded\n"
40 if($threads::shared::threads_shared);
41}
42
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43require Exporter;
44require DynaLoader;
45
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46our @ISA = qw(Exporter DynaLoader);
47
48our %EXPORT_TAGS = ( all => [qw()]);
49
50our @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
51
52our @EXPORT = qw(
53
54);
55our $VERSION = '0.05';
56
47ba8780 57
43d3ddbe 58sub equal {
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59 return 1 if($_[0]->tid() == $_[1]->tid());
60 return 0;
61}
62
8222d950 63$threads::threads = 1;
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64
65bootstrap threads $VERSION;
66
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67# why document 'new' then use 'create' in the tests!
68*create = \&new;
69
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70# Preloaded methods go here.
71
721;
73__END__
74
75=head1 NAME
76
77threads - Perl extension allowing use of interpreter based threads from perl
78
79=head1 SYNOPSIS
80
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81use threads;
82
83sub start_thread {
84 print "Thread started\n";
85}
86
9c4972d9 87my $thread = threads->create("start_thread","argument");
47ba8780 88
9c4972d9 89$thread->create(sub { print "I am a thread"},"argument");
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90
91$thread->join();
92
93$thread->detach();
94
95$thread = threads->self();
96
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97threads->tid();
98threads->self->tid();
99
100$thread->tid();
47ba8780 101
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102threads->yield();
103
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104=head1 DESCRIPTION
105
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106Perl 5.6 introduced something called interpreter threads. Interpreter
107threads are different from "5005threads" (the thread model of Perl
1085.005) by creating a new perl interpreter per thread and not sharing
109any data or state between threads.
11c51ed3 110
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111Prior to perl 5.8 this has only been available to people embedding
112perl and for emulating fork() on windows.
11c51ed3 113
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114The threads API is loosely based on the old Thread.pm API. It is very
115important to note that variables are not shared between threads, all
116variables are per default thread local. To use shared variables one
117must use threads::shared.
11c51ed3 118
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119It is also important to note that you preferably enable threads by
120doing C<use threads> as early as possible and that it is not possible
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121to enable threading inside an eval ""; In particular, if you are
122intending to share variables with threads::shared, you must
123C<use threads> before you C<use threads::shared> and threads will emit
124a warning if you do it the other way around.
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125
126=over
127
9c4972d9 128=item $thread = threads->create(function, LIST)
47ba8780 129
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130This will create a new thread with the entry point function and give
131it LIST as parameters. It will return the corresponding threads
132object.
47ba8780 133
11c51ed3 134=item $thread->join
47ba8780 135
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136This will wait for the corresponding thread to join. When it finishes
137join will return the return values of the entry point function. If a
138thread has been detached, join will return without wait.
47ba8780 139
11c51ed3 140=item $thread->detach
47ba8780 141
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142Will throw away the return value from the thread and make it
143non-joinable.
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144
145=item threads->self
146
147This will return the object for the current thread.
148
11c51ed3 149=item $thread->tid
47ba8780 150
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151This will return the id of the thread. threads->self->tid() is a
152quick way to get current thread id.
47ba8780 153
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154=item threads->yield();
155
156This will tell the OS to let this thread yield CPU time to other threads.
157However this is highly depending on the underlying thread implmentation.
158
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159=back
160
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161=head1 WARNINGS
162
163=over 4
164
165=item Cleanup skipped %d active threads
166
167The main thread exited while there were still other threads running.
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168This is not a good sign: you should either explicitly join the threads,
169or somehow be certain that all the non-main threads have finished.
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170
171=back
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172
173=head1 TODO
174
175=over
176
43d3ddbe 177=item Fix so the return value is returned when you join.
47ba8780 178
43d3ddbe 179=item Add join_all.
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180
181=item Fix memory leaks!
182
183=back
184
185=head1 AUTHOR and COPYRIGHT
186
11c51ed3 187Arthur Bergman E<lt>arthur at contiller.seE<gt>
47ba8780 188
43d3ddbe 189threads is released under the same license as Perl.
47ba8780 190
68795e93 191Thanks to
47ba8780 192
68795e93 193Richard Soderberg E<lt>rs at crystalflame.netE<gt>
ad91d581 194Helping me out tons, trying to find reasons for races and other weird bugs!
47ba8780 195
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196Simon Cozens E<lt>simon at brecon.co.ukE<gt>
197Being there to answer zillions of annoying questions
47ba8780 198
ad91d581 199Rocco Caputo E<lt>troc at netrus.netE<gt>
47ba8780 200
ad91d581 201Vipul Ved Prakash E<lt>mail at vipul.netE<gt>
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202Helping with debugging.
203
204please join perl-ithreads@perl.org for more information
205
206=head1 BUGS
207
208=over
209
210=item creating a thread from within a thread is unsafe under win32
211
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212=item PERL_OLD_SIGNALS are not threadsafe, will not be.
213
11c51ed3 214
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215=back
216
217=head1 SEE ALSO
218
11c51ed3 219L<perl>, L<threads::shared>, L<perlcall>, L<perlembed>, L<perlguts>
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220
221=cut