ODBCINSTINI

odbcinstini, commonly named odbcinst.ini, is the configuration file used by the ODBC Driver Manager to register ODBC drivers. It is INI-formatted and can be system-wide, typically /etc/odbcinst.ini, or user-specific, such as ~/.odbcinst.ini. The file defines drivers that can later be referenced by DSNs defined in odbc.ini.

Each driver is defined in a separate section labeled with a name in brackets, for example [ODBC Driver 17 for SQL Server]. Inside the section are key-value pairs that describe the driver and its setup. Core keys usually include Driver, which points to the shared library implementing the driver; Description, a human-readable name; and Setup, an optional path to a setup library. Additional options like UsageCount or FileUsage may appear on some systems.

The odbc.ini file, which holds DSNs, uses the Driver name defined in odbcinst.ini to locate and load the correct driver library at runtime. Together, these files allow a single driver to serve multiple DSNs across different databases and hosts.

Common operations include listing, adding, and removing driver definitions via the ODBC Admin Tool (for example, unixODBC’s odbcinst). Commands such as odbcinst -q -d list drivers, odbcinst -i -d -f template.ini install from a template, and odbcinst -r -d "DriverName" remove definitions. Direct edits to the INI files are also possible when appropriate permissions exist.

Example snippet:

[ODBC Driver 17 for SQL Server]

Description=Microsoft ODBC Driver 17 for SQL Server

Driver=/opt/microsoft/msodbcsql17/lib64/libmsodbcsql-17.so

Setup=/opt/microsoft/msodbcsql17/lib64/libmsodbcsql-17.so