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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC vs.
Revision 1.205 by root, Mon Jul 18 03:09:06 2011 UTC

168use common::sense; 168use common::sense;
169 169
170use base 'Exporter'; 170use base 'Exporter';
171 171
172BEGIN { 172BEGIN {
173 our $VERSION = '3.93'; 173 our $VERSION = '4.0';
174 174
175 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close 175 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
176 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx 176 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync aio_fsync 177 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync aio_fsync
178 aio_fdatasync aio_sync_file_range aio_fallocate 178 aio_fdatasync aio_sync_file_range aio_fallocate
1804=head2 FORK BEHAVIOUR 1804=head2 FORK BEHAVIOUR
1805 1805
1806Usage of pthreads in a program changes the semantics of fork 1806Usage of pthreads in a program changes the semantics of fork
1807considerably. Specifically, only async-safe functions can be called after 1807considerably. Specifically, only async-safe functions can be called after
1808fork. Perl doesn't know about this, so in general, you cannot call fork 1808fork. Perl doesn't know about this, so in general, you cannot call fork
1809with defined behaviour in perl. IO::AIO uses pthreads, so this applies, 1809with defined behaviour in perl if pthreads are involved. IO::AIO uses
1810but many other extensions and (for inexplicable reasons) perl itself often 1810pthreads, so this applies, but many other extensions and (for inexplicable
1811is linked against pthreads, so this limitation applies. 1811reasons) perl itself often is linked against pthreads, so this limitation
1812applies to quite a lot of perls.
1812 1813
1813Some operating systems have extensions that allow safe use of fork, and 1814This module no longer tries to fight your OS, or POSIX. That means IO::AIO
1814this module should do "the right thing" on those, and tries on others. At 1815only works in the process that loaded it. Forking is fully supported, but
1815the time of this writing (2011) only GNU/Linux supports these extensions 1816using IO::AIO in the child is not.
1816to POSIX. 1817
1818You might get around by not I<using> IO::AIO before (or after)
1819forking. You could also try to call the L<IO::AIO::reinit> function in the
1820child:
1821
1822=over 4
1823
1824=item IO::AIO::reinit
1825
1826Abondons all current requests and I/O threads and simply reinitialises all
1827data structures. This is not an operation suppported by any standards, but
1828happens to work on GNU/Linux and some newer BSD systems.
1829
1830The only reasonable use for this function is to call it after forking, if
1831C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in
1832the process will result in undefined behaviour. Calling it at any time
1833will also result in any undefined (by POSIX) behaviour.
1834
1835=back
1817 1836
1818=head2 MEMORY USAGE 1837=head2 MEMORY USAGE
1819 1838
1820Per-request usage: 1839Per-request usage:
1821 1840

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