symlink in binary `.deb` package - linux

When creating a binary .deb package
mypkg
/DEBIAN
- control
/path
/to
- mypkg.so
What is the best way to include a symlink to /path/to/mypkg.so from /some/other/path/mypkg.so?
Guidance from other threads has been to add a (lowercase) debian/links file, which didn't appear to have any effect (no link created on install).
I also tried using dh_link but it appears to expect source (vs binary) packages with a control file at debian/control and errors out with
dh_link: error: "debian/control" not found. Are you sure you are in the correct directory?

Related

How to make Cmake globally available

I just installed Cmake from git clone wget http://www.cmake.org/files/v2.8/cmake-2.8.3.tar.gz in a new folder on a Linux server. The compilation worked but cmake command is not recognized from other paths. Should I copy the entire contents of cmake-2.8.0 folder to usr/local/bin? Or is the contents of bin folder that need to be copied?
Thanks
On Linux and other Unix-based systems, a common arrangement is to install packages to /opt and add relevant entries to the PATH environment variable to make them available. This is intended for packages not provided by the native package manager or distribution. By choosing an appropriate directory structure, this can be done in a way which also allows different versions to be installed simultaneously and the user can pick which one they want by adding the relevant directory to the PATH.
For the specific case of CMake asked about in the question, you can use a directory structure like /opt/cmake/<version> and then add the relevant /opt/cmake/<version>/bin directory to your PATH (e.g. /opt/cmake/3.8.2/bin for the 3.8.2 CMake release). You can even just download the official pre-built CMake tarballs, unpack them and move the top level directory into the /opt/cmake area as the particular version you downloaded. I've used this successfully on Linux, MacOS and Solaris, as I'm sure have many others.
Note that once you've run CMake on a particular source tree, the cmake executable doesn't need to be on the PATH any more. If cmake needs to be re-run, the build will do so itself and it records the full path to the cmake executable in its own cache, so the PATH isn't even consulted (this is essential in ensuring the same version of CMake continues to be used for all builds regardless of the PATH, since PATH can change between login sessions, etc.). You would only need cmake on your PATH if you intend to invoke cmake manually or for the first time you run it on a source tree, but in both of these cases you can always just use the full path to the cmake executable if you preferred.
I should also add that the entire set of files provided in the CMake package are required, not just the bin directory. CMake makes extensive use of files in its other directories, such as the various modules it comes with. If you are building CMake from source, you may want to build the package target so you get a relocatable tarball or similar which will contain everything that should be included when you provide a CMake package on your system.
After the build, use 'sudo make install'. This will make sure the correct libraries and binaries are copied to their proper places.
Usually this will install the binary to /usr/local/bin.
Make sure the PATH variable has this included.
sudo make install did not copy to /usr/local/bin/ for some reason, so I copied the content of CMAKE /bin. to usr/local/bin an it worked.
cp –a bin/. /usr/local/bin/

dpkg-buildpackage error: missing files (usr/include/*)

I am trying to build a dev package out of some .so files - i.e libraries.
dh_make -f ../ mylibs.tar.gz
then I choose
-l
since I want a library package.
A debian folder is created which consists of among others the controlfile and the install file.
When I finally create the package with
dpkg-buildpackage
I get the following error message:
dh_install: mylibs-dev missing files (usr/include/*), aborting
I dont understand what is missing since the headers are copied to
usr/include
I have checked the directory and the headers are copied there. So why do I get this error message?
the install-file look like this:
usr/lib/lib*.so.*
So - may the path to usr/include be missing here? I've tried with
usr/include/h.*
but it does not work
The debian install files are most often used for source packages that produce several binary packages. In that case, dh_auto_install installs to the directory debian/tmp/ and dh_install moves the files from there to each package. However, when there is a single package, dh_auto_install takes a shortcut and installs directly to debian/package-name/. In that case, you only need to list in the install file the files that make install missed (usually none). If you list the regular, installed files, dh_install will get confused because it is still looking for them in debian/tmp/.
It is possible to override either the directory where dh_auto_install installs, or the directory where dh_install is looking, but you probably don't need either.

Files installed from debian package with dpkg do not belong to root

I created a binary package with this command:
dpkg-deb --build -z9 -Zlzma $(DEB_SRC_DIR) $(DEB_DEST_DIR)
and install it on my Ubuntu 12.04 with this command:
sudo dpkg -i /path/to/package
The contents of the package I think are irrelevant.
Despite the sudo command the files in the installation directory belong to the current user and not to root as I expected.
How can I fix that?
Try to run the dpkg-deb command with fakeroot:
`fakeroot dpkg-deb ...`
(This will only help if the files in the source directory already have the correct ownership, which they probably dont. The problem you're actually trying to solve here, is to create an archive with files in it that belong to user root, which is where fakeroot theoretically helps.)
Let me say though, that what you are doing is not the best way for creating a binary package (far from it).
Instead, create a debian/ directory with dh_make (from the dh-make package), and edit the control file and changelog accordingly. You also need a file debian/install that lists what files you are installing and where they should go. There are various guides on the net (and on Stack Overflow) that explain this process. For example, look at the Debian New Maintainers' Guide.
You can then use dpkg-buildpackage to create a real, standard-conforming Debian package with your files in a reproducible way.
dpkg-deb is a low-level tool for manipulating existing deb files; it's not meant to be used for package creation.

Can I avoid exporting LD_LIBRARY_PATH by hardcoding library paths in the executable?

I'm zipping a pre-built (no source/object files) binary application for distribution. The binary application requires a couple of libraries not included by default. The only way I seem to be able to get the application to start on the end-user is by including a run.sh that sets the library path to the current directory:
export LD_LIBRARY_PATH=./:$LD_LIBRARY_PATH
./MyApp.out
However, I'd really like to allow the user to just unzip the zip and doubleclick MyApp.out (without the shell script). Can I edit MyApp.out to search the current directory for the library? I've done something similar on OSX using install_name_tool, but that tool isn't available here.
You want to set the rpath. See this answer. So link using
gcc yourobjects*.o -L/some/lib/dir/ -lsome -Wl,-rpath,.
But you might want even to use -Wl,-rpath,$PWD or perhaps -Wl,-rpath,'$ORIGIN'. See this.
You could also (and this should work for a pre-built executable) configure your /etc/ld.so.conf by adding a line there with an absolute path (of the directory containing the lib), then running ldconfig -v ... See ldconfig(8)
I would suggest adding /usr/local/lib into /etc/ld.so.conf and making a symlink from /usr/local/lib/libfoo.so to e.g. $HOME/libfoo.so etc... (then run ldconfig ...). I don't think adding a user specific directory to /etc/ld.so.conf is reasonable ...
PS. What you really want is to package your application (e.g. as a *.deb package for Debian or Ubuntu, or an *.rpm for Fedora or Redhat). Package management systems handle dependencies!

Run time installation directory of debian package contents

I have a debian package that I built that contains a tar ball of the files, a control file, and a postinst file. Its built using dpkg-deb and it installs properly using dpkg.
The modification I would like to make is to have the installation directory of the files be determined at runtime based on an environment variable that will be set when dpkg -i is run on the deb file. I echo out the environment variable in the postinst script and I can see that its set properly.
My questions:
1) Is it possible to dynamically determine the installation directory at runtime?
2) If its possible how would I go about this? I have read about the rules file and the mypackage.install files but I don't know if either of these would allow me to accomplish this.
I could hack it by copying the files to the target location in the posinst script but I would prefer to do it the right way if possible.
Thanks in advance!
So this is what I found out about this problem over the past couple of weeks.
With prepackaged binaries you can't build a debian package with a destination directory dynamicall determined at runtime. I believe that this might be possible if installing a package that is built from source where you can set the install directory using configure. But in this case since these are embedded Ubuntu machines they don't have make so I didn't pursue such an option. I did work out a non traditional method (hack) for installing that did work. Since debian packages simply contain a tar ball relative to / simply build your package relative to a directory under /tmp. In the postinst script you can then determine where to copy the files from the archive into a permanent location.
I expected that after rebooting and the automatic deletion of the subdirectory under /tmp that dpkg might not know that the file package existed. This wasn't a problem. When I ran 'dpkg -l myapp' it showed as still installed. Updating the package using dpkg/apt-get also worked without a hitch.
What I did find is that if you attempted to remove the package using 'dpkg -r myapp' that dpkg would try and remove /tmp which wasn't good. However /tmp isn't easily removed so it never succeeded. Plus in our situation we never remove packages but instead simply upgrade them.
I eventually had to abandon the universal package due to code differences in the sources resulting in having to recompile per platform but I would have left it this way and it did work.
I tried using --instdir to change the install directory of the package and it does relocate the files but dpkg fails since the dpkg file can't be found relative to the new instdir. Using --instdir is sort of like a chroot. I also tried --admindir and --root in various combinations to see if I could use the dpkg system relative to / but install relocate the files but they didn't work. I guess rpm has a relocate option that works but not Ubuntu.
You can also write a script that runs dpkg-deb with a different environment for 6 times, generating 6 different packages. When you make a modification, you simply have to run your script, and all 6 packages gets generated and you can install them on your machines avoiding postinst hacking!
Why not install to a standard location, and simply use a postinst script to create symbolic links to the desired location? This is much cleaner, and shouldn't break anything in dpk -I.

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