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=head1 NAME | ||
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Imager::Threads - Imager and threads | ||
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=head1 SYNOPSIS | ||
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use Imager; | ||
use threads; | ||
Imager->preload; | ||
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threads->create(...); | ||
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=head1 DESCRIPTION | ||
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Starting from version 0.93 Imager attempts to work safely with perl's | ||
C<ithreads>. | ||
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Previous versions stored some state in global variables, in particular | ||
the internal error stack. | ||
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However there are some limitations: | ||
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=over | ||
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=item * | ||
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Imager's debug malloc isn't thread safe and will never be. Imager's | ||
debug malloc is disabled by default. | ||
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=item * | ||
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C<libtiff>, which Imager uses for TIFF file support is not thread | ||
safe, C<Imager::File::TIFF> works around this by single-threading its | ||
access to C<libtiff>. | ||
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=item * | ||
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C<giflib>, which Imager uses for GIF support is not thread safe before | ||
version 5. C<Imager::File::GIF> works around this by single threading | ||
its access to C<giflib>. | ||
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=item * | ||
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killing a thread reading or writing TIFF or GIF files may deadlock | ||
other threads when they attempt to read or write TIFF or GIF files. | ||
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=back | ||
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Note that if you have another module using C<libtiff> or C<giflib> it | ||
may interact with Imager's use of those libraries in a threaded | ||
environment, since there's no way to co-ordinate access to the global | ||
information C<libtiff> and C<giflib> maintain. | ||
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Imager currently doesn't use threads itself. | ||
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=head1 SEE ALSO | ||
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Imager, C<threads> | ||
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=head1 AUTHOR | ||
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Tony Cook <tony@cpan.org> | ||
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=cut |