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Re: Avoid collisions between parallel [...], take 2
On Thu, Oct 29, 2009 at 04:17:29PM +0100, Corinna Vinschen wrote:
>On Oct 22 13:55, Corinna Vinschen wrote:
>> Ok, so, after all the discussions, this is the patch which comes
>> out of it. [...]
>I just created the matching documentation, see below. I hope that's
>Is there anything else which holds up the inclusion of this patch?
I haven't had time to look at the patch itself but don't let that hold up
the checkin. I assume other people have checked it for any gotchas.
I have some wording changes below, however.
>RCS file: /cvs/src/src/winsup/doc/new-features.sgml,v
>retrieving revision 1.21
>diff -u -p -r1.21 new-features.sgml
>--- doc/new-features.sgml 28 Oct 2009 10:09:54 -0000 1.21
>+++ doc/new-features.sgml 29 Oct 2009 15:15:25 -0000
>@@ -325,6 +325,14 @@
> delete, to support the toolchain in implementing full C++ standards
> conformance when working with shared libraries.
>+- Different Cygwin installations in different paths can be run in parallel
>+ without knowing of each other. The path of the Cygwin DLL used in a
>+ process is a key used when creating IPC objects. So different Cygwin
>+ DLLs are running in different namespaces.
>+- Each Cygwin DLL stores its path and installation key in the registry.
>+ This allows to troubleshoot problems which could be a result of having
This allows troubleshooting of problems...
>+ multiple concurrent Cygwin installations.
>RCS file: /cvs/src/src/winsup/utils/utils.sgml,v
>retrieving revision 1.79
>diff -u -p -r1.79 utils.sgml
>--- utils/utils.sgml 22 Jul 2009 10:20:26 -0000 1.79
>+++ utils/utils.sgml 29 Oct 2009 15:15:25 -0000
>@@ -13,13 +13,18 @@ command-line utilities support the <lite
> <sect2 id="cygcheck"><title>cygcheck</title>
>-Usage: cygcheck PROGRAM [ -v ] [ -h ]
>- cygcheck -c [ PACKAGE ... ] [ -d ]
>- cygcheck -s [ -r ] [ -v ] [ -h ]
>+Usage: cygcheck [-v] [-h] PROGRAM
>+ cygcheck -c [-d] [PACKAGE]
>+ cygcheck -s [-r] [-v] [-h]
> cygcheck -k
>- cygcheck -f FILE [ FILE ... ]
>- cygcheck -l [ PACKAGE ... ]
>+ cygcheck -f FILE [FILE]...
>+ cygcheck -l [PACKAGE]...
> cygcheck -p REGEXP
>+ cygcheck --delete-orphaned-installation-keys
>+ cygcheck --enable-unique-object-names Cygwin-DLL
>+ cygcheck --disable-unique-object-names Cygwin-DLL
>+ cygcheck --show-unique-object-names Cygwin-DLL
>+ cygcheck -h
> List system information, check installed packages, or query package database.
> At least one command option or a PROGRAM is required, as shown above.
>@@ -36,6 +41,19 @@ At least one command option or a PROGRAM
> -l, --list-package list contents of PACKAGE (or all packages if none given)
> -p, --package-query search for REGEXP in the entire cygwin.com package
> repository (requires internet connectivity)
>+ Delete installation keys of old, now unused
>+ installations from the registry. Requires the right
>+ to change the registry.
>+ --enable-unique-object-names Cygwin-DLL
>+ --disable-unique-object-names Cygwin-DLL
>+ --show-unique-object-names Cygwin-DLL
>+ Enable, disable, or show the setting of the
>+ \"unique object names\" setting in the Cygwin DLL
>+ given as argument to this option. The DLL path must
>+ be given as valid Windows(!) path.
>+ See the users guide for more information.
>+ If you don't know what this means, don't change it.
> -v, --verbose produce more verbose output
> -h, --help annotate output with explanatory comments when given
> with another command, otherwise print this help
>@@ -184,6 +202,65 @@ for example:</para>
> <prompt>$</prompt> <userinput>cygcheck -s -v -r -h > cygcheck_output.txt</userinput>
>+Each Cygwin DLL stores its path and installation key in the registry.
>+This allows to troubleshoot problems which could be a result of having
troubleshooting of problems...
>+multiple concurrent Cygwin installations. However, if you're experimenting
>+a lot with different Cygwin installation paths, your registry could
>+accumulate a lot of old Cygwin installation entries for which the
>+installation doesn't exist anymore. To get rid of these orphaned registry
>+entries, use the <command>cygcheck --delete-orphaned-installation-keys</command>
>+Each Cygwin DLL generates a key value from its installation path. This
>+value is not only stored in the registry, it's also used to generate
>+global object names used for interprocess communication. This allows
>+to keep different Cygwin installations separate. Processes running
This keeps different Cygwin installations separate.
>+under a Cygwin DLL installed in C:\cygwin don't see processes running
>+under a Cygwin DLL installed in C:\Program Files\cygwin. This allows
>+to run multiple versions of Cygwin DLLs without these versions to
>+interfere with each other, or to run small third-party installations
>+for a specific purpose independently from a Cygwin net distribution.
>+For debugging purposes it could be desired that the various Cygwin DLLs
>+use the same key, independently from their installation paths. If the
>+DLLs have different versions, trying to run processes under these DLLs
>+concurrently will result in error messages like this one:</para>
>+*** shared version mismatch detected - 0x8A88009C/0x75BE0074.
>+This problem is probably due to using incompatible versions of the cygwin DLL.
>+Search for cygwin1.dll using the Windows Start->Find/Search facility
>+and delete all but the most recent version. The most recent version *should*
>+reside in x:\\cygwin\\bin, where 'x' is the drive on which you have
>+installed the cygwin distribution. Rebooting is also suggested if you
>+are unable to find another cygwin DLL.
>+To disable the usage of a unique key value of a certain Cygwin DLL, use
>+the <command>cygcheck --disable-unique-object-names Cygwin-DLL</command>
>+command. <literal>Cygwin-DLL</literal> is the Windows path (*not* a
>+Cygwin POSIX path) to the DLL for which you want to disable this feature.
>+Note that you have to stop all Cygwin processes running under this DLL,
>+before you're allowed to change this setting. For instance, run
>+<command>cygcheck</command> from a DOS command line for this purpose.</para>
>+<para>To re-enable the usage of a unique key, use the
>+<command>cygcheck --enable-unique-object-names Cygwin-DLL</command> command.
>+This option has the same characteristics as the
>+<para>Last but not least, you can use
>+<command>cygcheck --show-unique-object-names Cygwin-DLL</command> to find out
>+if the given Cygwin DLL use unique object names or not. In contrast to the
>+<literal>--disable-...</literal> and <literal>--enable-...</literal> options,
>+the <literal>--show-unique-object-names</literal> option also works for
>+Cygwin DLLs which are currently in use.</para>
> <sect2 id="cygpath"><title>cygpath</title>