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Using the Windows PID as Cygwin PID has a few drawbacks: - the PIDs on Windows get reused quickly. Some POSIX applications choke on that, so we need extra code to avoid too quick PID reuse. - The code to avoid PID reuse keeps parent process handles and (depending on a build option) child processes open unnecessarily. - After an execve, the process has a split personality: Its Windows PID is a new PID, while its Cygwin PID is the PID of the execve caller process. This requires to keep two procinfo shared sections open, the second just to redirect process info requests to the first, correct one. This patch changes the way Cygwin PIDs are generated: - Cygwin PIDs are generated independently of the Windows PID, in a way expected by POSIX processes. The PIDs are created incrementally in the range between 2 and 65535, round-robin. - On startup of the first Cygwin process, choose a semi-random start PID for the first process in the lower PID range to make the PIDs slightly unpredictable. This may not be necessary but it seems kind of inviting to know that the first Cygwin process always starts with PID 2. - Every process not only creates the shared procinfo section, but also a symlink in the NT namespace, symlinking the Windows PID to the Cygwin PID. This drops the need for the extra procinfo section after execve. - Don't keep other process handles around unnecessarily. - Simplify the code creating/opening the shared procinfo section and make a clear distinction between interfaces getting a Cygwin PID and interfaces getting a Windows PID. 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.