.CLEO File Extension

Plugin file used as part of the CLEO library, which is used for executing modifications to some Grand Theft Auto series games; stores a library in the Dynamic Link Library (.DLL) format and enables "opcodes" which can be scripted to alter game content.

CLEO plugins should be installed to the \CLEO\ directory within the GTA SA installation directory. When the game runs at startup, the CLEO library scans for plugins and runs them.

Some common CLEO files include:

• IniFiles.cleo: contains opcodes that can be used in INI files.
• FileSystemOperations.cleo: stores opcodes for operating on files and folders.
• IntOperations.cleo: enables logical operators, such as AND, OR, and XOR.