math-linux.com

SVN — Branch, Branching subversion howto

Nadir SOUALEM — 2010-05-26T09:39:22Z

Requirements

I suppose here your server is based on svn over ssh (svn+ssh), you can easily replace svn+ssh by https if you use Webdav for example.

svn+ssh://your/server/...
 https://your/server/...

Creating the branch

Choose a branche name for example, MyBranch. Create the branch in the repository by copying the trunk:

$ svn copy svn+ssh://your/server/trunk svn+ssh://your/server/branches/MyBranch
 Committed revision 3328.

Remember this commited revision number 3328.

If you have a local copy you do not need to checkout your branch just switch:

$ cd /your/local/copy
 $ svn switch svn+ssh://your/server/branches/MyBranch .

Do not forget the dot at endline.

If you do not have a local copy you, checkout your branch:

$ mkdir /your/local/copy
 $ cd /your/local/copy
 $ svn checkout svn+ssh://your/server/branches/MyBranch .

Check if the localization is ok:

$ svn info | grep MyBranch
 URL: svn+ssh://your/server/branches/MyBranch

Now you can work with your branch exactly as working on the trunk. (update, commit, etc ...).

Merge with the trunk

You've been developing on your branch, and so have other people on trunk, and now you have to add their changes to your branch.

$ cd /your/local/copy
 $ svn update
 At revision 3269.

Add their changes to your branch:

$ svn merge -r3328:3269 svn+ssh://your/server/trunk .
 U src/file.cpp
 U src/file.h

This command finds all the changes in revisions 3329, 3330, ... , 3269 that were made in the trunk, and applies them in Mybranch.

Now you must commit these changes to your branch repository; with appropriate comments to remember which range you have already merged:

$ svn ci -m "Merged the trunk from 3328 to 3269." .
 Sending src/file.cpp
 Sending src/file.h
 Transmitting file data ..
 Committed revision 3270.

After another interval of work, you will have to merge again to get the new changes. You specify a revision range that takes only the changes you haven't already merged:

$ cd /your/local/copy
 $ svn update
 At revision 3333.

Add their changes to your branch:

$ svn merge -r3269:3333 svn+ssh://your/server/trunk .
 U src/file.cpp
 U src/file.h

This command finds all the changes in revisions 3370, 3371, ... , 3333 that were made in the trunk, and applies them in Mybranch.

Now you must commit these changes to your branch repository:

$ svn ci -m "Merged the trunk from 3269 to 3333." .
 Sending src/file.cpp
 Sending src/file.h
 Transmitting file data ..
 Committed revision 3334.

Back to the trunk

Once you have finished your branch and you have merged again the last change from the trunk, you will commit your branch back to the trunk. Remember! MyBranch was created at revision number 3328. Now you have to add all your changes to the trunk.

$ cd /your/local/copy
 $ svn update
 At revision 3400.

Switch to the trunk and merge from Mybranch all the changes(3328:3400) to the trunk

$ svn switch svn+ssh://your/server/trunk

Check if the relocalization is ok:

$ svn info | grep MyBranch
 URL: svn+ssh://your/server/trunk

Add all your changes to the trunk

$ svn merge -r3328:3400 svn+ssh://your/server/branches/MyBranch .

Now you must commit these changes to the trunk:

$ svn ci -m "branch back MyBranch into trunk" .
 Sending src/file.cpp
 Sending src/file.h
 Transmitting file data ..
 Committed revision 3334.

Delete your branch

At last, delete your branch

svn del svn+ssh://your/server/branches/MyBranch

C++ — extern, extern "C" — mangling

Nadir SOUALEM — 2010-05-12T19:58:26Z

extern keyword can be used as
a storage class specifier for a variable
to tell the compiler how to link to an external function.

extern

The extern keyword is used to inform the compiler about variables declared outside of the current scope. Variables described by extern statements will not have any space allocated for them, as they should be properly defined elsewhere.

Extern statements are frequently used to allow data to span the scope of multiple files. An external variable must be defined, exactly once, outside of any function.

extern "C" and mangling

Since C++ has overloading of function names and C does not, the C++ compiler cannot just use the function name as a unique id to link to, so it mangles the name by adding information about the arguments. A C compiler does not need to mangle the name since you can not overload function names in C. When you state that a function has extern "C" linkage in C++, the C++ compiler does not add argument/parameter type information to the name used for linkage. For example test.cpp

foo function is decorated. Now with test.cpp

foo function is not decorated.

If you want to mix C and C++ code add the following guards in your C code.

This allows to have the good decoration when you link with the C/C++ libraries.

Comment installer un package Latex ?

Nadir SOUALEM — 2010-05-07T12:13:10Z

Dans un premier temps vous devez être root ! Supposons que nous voulions installerl e package My_package. Créez un répertoire My_package et copier tout les fichiers de style à l'intérieur :

Mettez à jour votre base de données

Dans votre fichier Latex, ajoutez alors

Et le tour est joué !!!

How to install latex package ?

Nadir SOUALEM — 2010-05-07T12:08:57Z

First you must be root ! We want to install the package My_package. Create a directory My_package and copy all style files in:

Update your database with

In your latex file, add

Enjoy !!!

SVN — Comment ignorer des fichiers ou des répertoires avec subversion ?

Nadir SOUALEM — 2010-05-02T19:36:09Z

Ignorer un fichier

Pour ignorer tous les fichiers d'extension .o, utilisez :

Ignorer un répertoire

Pour ignorer le répertoire tmp

Ignorer plusieurs fichiers ou répertoires

Pour ignorer les répertoires tmp,obj,bin ainsi que les fichiers d'extension *.o *.lib,*.la. Sauvez le fichier suivant sous

svnignore.txt, et la commande suivante fera le boulot !!!

Ignorer plusieurs fichiers ou répertoires via la ligne de commande

Vous pourrez alors modifier la liste des fichiers ou répertoires à bannir.

Trouver les fichiers qui ne sont pas sous controle de version

Pour déterminer de tels fichiers :

SVN — How to ignore file or directory in subversion?

Nadir SOUALEM — 2010-05-02T19:14:05Z

Ignore file

To ignore all files with the ending .o use:

Ignore dir

If you want to ignore folder tmp

Ignore multiple files/dirs

If you want to ignore tmp,obj,bin dirs and all files with *.o *.lib,*.la extension. Save this file

and name it svnignore.txt, the following command will do the job !

Ignore multiple files/dirs via command line

This will bring up list of files or directories to ignore.

Find files that are not under version control

To find such files:

How to patch metis-4.0 error: conflicting types for __log2

Nadir SOUALEM — 2010-04-30T08:16:20Z

METIS is a set of serial programs for partitioning graphs, partitioning finite element meshes, and producing fill reducing orderings for sparse matrices. The algorithms implemented in METIS are based on the multilevel recursive-bisection, multilevel k-way, and multi-constraint partitioning schemes. I give a patch for metis-4.0 software, compilation fails with gcc 4.4.x

nsoualem@gold: -> cd metis-4.0
 nsoualem@gold: -> make
 (cd Lib ; make ) 
 make[1]: Entering directory `/home/nsoualem/test/lib_ext/lib_ext/metis-4.0/Lib'
 cc -O2 -I. -c coarsen.c
 In file included from ./metis.h:36,
 from coarsen.c:13:
 ./proto.h:462: error: conflicting types for '__log2'
 /usr/include/bits/mathcalls.h:145: note: previous declaration of '__log2' was here
 make[1]: *** [coarsen.o] Error 1
 make[1]: Leaving directory `/home/nsoualem/test/lib_ext/lib_ext/metis-4.0/Lib'
 make: *** [default] Error 2

This error is due to the duplication of __log2 /usr/include/bits/mathcalls.h:145

Here is the patch to get compilation successful

nsoualem@gold: -> cd metis-4.0
 nsoualem@gold: -> patch -p1 < metis-4.0.patch

Comment extraire le nom et l'extension d'un fichier en Bash

Nadir SOUALEM — 2010-04-29T14:21:20Z

nsoualem@gold: -> PICTURE=Tux.jpg
 nsoualem@gold: -> echo ${PICTURE%%.*}
 Tux
 nsoualem@gold: -> echo ${PICTURE#*.}
 jpg

Dans le cas de multiples extensions :

nsoualem@gold: -> FILE=archive.tar.gz
 nsoualem@gold: -> echo ${FILE%%.*}
 archive
 nsoualem@gold: -> echo ${FILE%.*}
 archive.tar
 nsoualem@gold: -> echo ${FILE#*.}
 tar.gz
 nsoualem@gold: -> echo ${FILE##*.}
 gz

How to Get or Extract filename and extension in bash

Nadir SOUALEM — 2010-04-29T14:19:22Z

nsoualem@gold: -> PICTURE=Tux.jpg
 nsoualem@gold: -> echo ${PICTURE%%.*}
 Tux
 nsoualem@gold: -> echo ${PICTURE#*.}
 jpg

For multiples extensions files:

nsoualem@gold: -> FILE=archive.tar.gz
 nsoualem@gold: -> echo ${FILE%%.*}
 archive
 nsoualem@gold: -> echo ${FILE%.*}
 archive.tar
 nsoualem@gold: -> echo ${FILE#*.}
 tar.gz
 nsoualem@gold: -> echo ${FILE##*.}
 gz

How to find out my dns server addresses ?

Nadir SOUALEM — 2010-04-02T11:59:35Z

How to find out my dns server addresses ? To find your DNS server address type following command as shell prompt: $ cat /etc/resolv.conf # Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8) # DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN nameserver xxx.xxx.xxx.xxx nameserver xxx.xxx.xxx.xxx - Network / dns, resolv.conf