Error Message

• "./Iguana: error while loading shared libraries: libidn.so.11: cannot open shared object file: No such file or directory”

• Or alternatively, "./msgtransform: error while loading shared libraries: libidn.so.11: cannot open shared object file: No such file or directory”

Usually, this error message happens when you try to launch Iguana/Chameleon via the command line on Linux. This is more prevalent on newer and more up-to-date Linux distributions.

Issue

• Most new distributions of Linux come downloaded with libidn2 rather than libidn. This is a problem because Iguana and Chameleon both use libidn to run.

• It seems also that versions above 1.34 for libidn might have different file names (for example, “libidn.so.12” rather than “libidn.so.11”)

Solution

Option 1: Download the library, depending on the package manager (for example, dnf (yum), apt), you may be able to download the library.

To search for the library:

sudo dnf search libidn
OR (depending on your package manager)
sudo apt search libidn

Depending on the results from the command above, the following installation commands may change slightly but the format remains essentially the same.

Let’s assume that the previous command showed us that there is a libidn.x86_64 package that we can download on a Redhat machine - line 3 uses the library name found on Fedora-based Linux but not Redhat machines:

64-bit:

sudo dnf install libidn.x86_64
(If the line 1 command doesn't work, try the one on line 3)
sudo dnf install libidn1.34.x86_64

OR 32-bit:

sudo dnf install libidn.i686
(If the line 1 command doesn't work, try the one on line 3)
sudo dnf install libidn1.34.i686

This should allow you to download the library and install the desired modules.

Option 2: If there is a newer version of the shared file available but from the same iteration (libidn rather than libidn2) then you can try creating a symbolic to libidn.so.11 from libidn.so.12. In other words, whenever something uses/calls for libidn.so.11 it actually uses libidn.so.12. You can do this by using this command (please make sure the pathing is correct for libidn.so.12):

sudo ln -s /usr/lib/x86_64-linux-gnu/libidn.so.12 /usr/lib/x86_64-linux-gnu/libidn.so.11

However, while we’ve seen it fix this issue, this is NOT recommended as it can lead to compatibility issues and might cause unspecified and undefined behaviour.