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Using posix timers "timer_tracker" as base class for timerfd was flawed. Posix timers are not inherited by child processes and don't survive execve. The method used by posix timers didn't allow to share timers between processes. The timers were still per-process timers and worked entirely separate from each other. Reading from these timers via different descriptors was only synchronized within the same process. This does not reflect the timerfd semantics in Linux: The per-file timers can be dup'ed and survive fork and execve. They are still just descriptors pointing to the same timer object originally created by timerfd_create. Synchronization is performed between all descriptor instances of the same timer, system-wide. Thus, reimplement timerfd using a timer instance in shared memory, a kernel timer, and a handful of sync objects. Every process maintains a per-process timerfd struct on the cygheap maintaining a per-process thread. Every process sharing the same timerfd will run this thread checking the state of the timer, similar to the posix timer thread, just working on the shared objects and synchronizing its job with each other thread. Drop the timerfd implementation in the posix timer code and move the public API to fhandler_timerfd.c. Keep the ttstart timer_tracker anchor out of "NO_COPY" since the fixup_after_fork code should run to avoid memory leakage. Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.