+ 2013/04/09 version 2013.07 Require IO::Event version 0.812 to work around a FreeBSD issue. + 2013/04/05 version 2013.06 Added File::Flock::Forking to auto-select between File::Flock and File::Flock::Subprocess. Added File::Flock::Subprocess for machines that don't propogate locks across fork(). POD is now after __END__ instead of __DATA__. Oops! + 2008/03/27 version 2008.01 Joshua Kronengold, mneme at io dot com, sent in a patch to use IO::File instead of the $gensym hack. Applied. Carl Fürstenber, azatoth at gmail dot com and others requested that license terms be spelled out. Done. + 2004/11/19 Bugfix in &unlock for if the lock file has been removed. Bugfix by Vadim O. Ustiansky . + 2001/06/05 Added $av0debug variable to note locking attempts in $0 + 2001/05/18 Added lock_rename to the EXPORT list. + 2000/09/25 Added tests to make sure 'nonblocking' works + 1999/12/17 Added the lock_rename() function. + 1999/06/22 SunOS systems seem to fail with EWOULDBLOCK on locked files. + 1999/06/21 It appears that on some systems (HP-UX) a blocking call to flock() can fail with EACCES instead of EAGAIN. + 1999/06/15 Perl changes. File::Flock must change to keep up. A call to lock() had to be changed to &lock(). Why? + 1998/12/01 More fixes for Solaris. Modified the unlock() function so that it can be called as a reference. + 1998/11/30 Fixed the object-style interface. Attempt to fix a double-unlock bug that makes the Linux port unhappy + 1998/11/26 Chaged O_RDONLY to O_RDWR for all file opens because Solaris won't let you get an exclusive lock on a read-only file. Crazy! Change suggested by Lupe Christoph . Thanks! Rewrote the handling of the removal of files created just so that they could be locked. Also tried to make sure that now file descriptors could get leaked.