OSSP cfg is a ISO-C library for parsing arbitrary C/C++-style configuration files. A configuration is sequence of directives, each directive consists of zero or more tokens, and each token can be either a string or again a complete sequence. This means the configuration syntax has a recursive structure and allows you to create configurations with arbitrarily-nested sections. The configuration syntax also provides complex single/double/balanced quoting of tokens, hexadecimal/octal/decimal character encodings, character escaping, C/C++ and shell-style comments, etc. The library API allows importing of a configuration text into an Abstract Syntax Tree (AST), traversing the AST, and optionally exporting the AST again as a configuration text.