Menu
We can change RPATH or RUNPATH of a binary file by using the chrpath tool. Note that you cannot convert a RUNPATH back to RPATH. Note that the string of the new set of paths should be smaller or equal to the length of what was stored earlier in the binary.
To create an RPATH entry, you simply tell it to the linker (not the compiler!), so for instance you could add to your ./configure call the string LDFLAGS=-Wl,-rpath,/my/software/base/my/lib/. libs to build and run against a specific version of your library.
What is RPATH and $ORIGIN. RPATH stands for run-time search path. According to Wikipedia, “rpath designates the run-time search path hard-coded in an executable file or library.
In computing, rpath designates the run-time search path hard-coded in an executable file or library. Dynamic linking loaders use the rpath to find required libraries. Specifically, it encodes a path to shared libraries into the header of an executable (or another shared library).
There is a more universal tool than chrpath called patchelf. It was originally created for use in making packages for Nix and NixOS (packaging system and a GNU/Linux distribution).
In case there is no rpath in a binary (here called rdsamp), chrpath fails:
chrpath -r '$ORIGIN/../lib64' rdsamp
rdsamp: no rpath or runpath tag found.
On the other hand,
patchelf --set-rpath '$ORIGIN/../lib64' rdsamp
succeeds just fine.
There is a tool called chrpath which can do this - it's probably available in your distribution's packages.
Just like @user7610 said, the right way to go is the patchelf tool.
But, I feel that I can give a more comprehensive answer, covering all the commands one needs to do exactly that.
For a comprehensive article on the subject, click here
First of all, many developers talk about RPATH, but they actually mean RUNPATH. These are two different optional dynamic sections, and the loader handles them very differently. You can read more about the difference between them in the link I mentioned before.
For now, just remember:
RUNPATH is set, RPATH is ignoredRPATH is deprecated and should be avoidedRUNPATH is preferred because it can be overridden by LD_LIBRARY_PATH
See the current R[UN]PATH
readelf -d <path-to-elf> | egrep "RPATH|RUNPATH"
Clear the R[UN]PATH
patchelf --remove-rpath <path-to-elf>
Notes:
RPATH and RUNPATH
Add values to R[UN]PATH
patchelf [--force-rpath] --set-rpath "<desired-rpath>" <path-to-elf>
Notes:
<desired-path> is a colon separated directories list, e.g: /my/libs:/my/other/libs
--force-rpath, sets RPATH, otherwise sets RUNPATH
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With