[SOLVED] How to install a library

apt-file search libmysqlclient.so
libmariadb-dev-compat: /usr/lib/x86_64-linux-gnu/libmysqlclient.so
libmariadbclient-dev-compat: /usr/lib/x86_64-linux-gnu/libmysqlclient.so

How to install the library libmysqlclient.so
or the library libmysqlclient.so.18

Originally Posted by droid.c3p0 apt-file search libmysqlclient.so libmariadb-dev-compat: /usr/lib/x86_64-linux-gnu/libmysqlclient.so libmariadbclient-dev-compat: /usr/lib/x86_64-linux-gnu/libmysqlclient.so How to install the library libmysqlclient.so or the library libmysqlclient.so.18

It would help if you actually told us which Linux distribution you're using, and what you are trying to do that involves this library needing to be installed. Since you post the apt-file command, it suggests you're using Debian based packages (.deb packages), and therefore likely a Debian based distribution.

The "general answer" to your question would be to find out which package contains this library, and install it (the mysql package perhaps?). One of those files is a symlink pointing to the same library rather than two different libraries (probably libmysqlclient.so is the symlink in this case).

I am using MX Linux - 18.
I am trying to write a simple programm with Code Typhon IDE, using a component of type TMySQL56Connection. When I try to connect to MySQL database on the hosting, I have message from Code Typhon Compiler: 'Can not load default MySQL library ("libmysqlclient.so.18" or "libmysqlclient.so"). Check your installation.'
I think, that I need to install above library(es).

While not an MX Linux user myself, from my searches, it seems you may need to enable the "MX Community Main" and/or "Test Repo". I did find a package for MX Linux in the "Test Repo" here (libmysqlclient18_5.6.30-1mx150+1_amd64.deb) - I haven't looked in the other online repo listed here though.

Try enabling the appropriate repo in one of your sources.list files, then you can use your package manager to install it.

Install libmysqlclient.so.18 : # apt install libmysqlclient18
https://packages.debian.org/jessie/libmysqlclient18
.... if it's still available for MX.
I.e. libmysqlclient18 is the old mysql-5.5.

And libmysqlclient.so : # apt install libmysqlclient-dev
Warning : You will probably get a later version.

Alternatively you can download the old packages and rebuild to
compat-libmysqlclient18_5.5.62_amd64.deb, compat-libmysqlclient-dev_5.5.62_amd64.deb

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