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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.196 by root, Fri Jun 10 06:50:42 2011 UTC vs.
Revision 1.199 by root, Wed Jun 29 12:46:36 2011 UTC

… …
168use common::sense; 168use common::sense;
169 169
170use base 'Exporter'; 170use base 'Exporter';
171 171
172BEGIN { 172BEGIN {
173 our $VERSION = '3.9'; 173 our $VERSION = '3.92';
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_sync aio_fsync 177 aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
178 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead 178 aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
… …
1789 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => 1789 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
1790 \&IO::AIO::poll_cb); 1790 \&IO::AIO::poll_cb);
1791 1791
1792=head2 FORK BEHAVIOUR 1792=head2 FORK BEHAVIOUR
1793 1793
1794This module should do "the right thing" when the process using it forks: 1794Usage of pthreads in a program changes the semantics of fork
1795considerably. Specifically, only async-safe functions can be called after
1796fork. Perl doesn't know about this, so in general, you cannot call fork
1797with defined behaviour in perl. IO::AIO uses pthreads, so this applies,
1798but many other extensions and (for inexplicable reasons) perl itself often
1799is linked against pthreads, so this limitation applies.
1795 1800
1796Before the fork, IO::AIO enters a quiescent state where no requests 1801Some operating systems have extensions that allow safe use of fork, and
1797can be added in other threads and no results will be processed. After 1802this module should do "the right thing" on those, and tries on others. At
1798the fork the parent simply leaves the quiescent state and continues 1803the time of this writing (2011) only GNU/Linux supports these extensions
1799request/result processing, while the child frees the request/result queue 1804to POSIX.
1800(so that the requests started before the fork will only be handled in the
1801parent). Threads will be started on demand until the limit set in the
1802parent process has been reached again.
1803
1804In short: the parent will, after a short pause, continue as if fork had
1805not been called, while the child will act as if IO::AIO has not been used
1806yet.
1807 1805
1808=head2 MEMORY USAGE 1806=head2 MEMORY USAGE
1809 1807
1810Per-request usage: 1808Per-request usage:
1811 1809

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