A SUPPORTING LIBRARY OF SOFTWARE TOOLS FOR CIF AND DDL 2. John Westbrook and Shu-Hsin Hsieh, Department of Chemistry, Rutgers University, Piscataway, NJ 08855-0939

A Data Description Language (DDL) provides the framework for the construction of comprehensive dictionaries of terminology such as the macromolecular CIF (mmCIF) dictionary. The DDL also provides features which may be used by software to perform rigorous validation of CIF dictionaries and CIF data files. A software library (CIFLIB) that is based on DDL 2 and provides simple and convenient access to information in CIF dictionaries and data files will be described. This library contains a collection of high level functions to process and check data stored in CIF format using the full detail of the mmCIF dictionary.

CIFLIB provides a C language application program interface which encapsulates all I/O operations and integrity checking on CIF dictionaries and data files from a calling application. Some of the functions provided by CIFLIB include: read and write operations on CIF format data files and dictionaries; read and write access to individual data items; detailed integrity checks on CIF data files and dictionaries; robust error handling; and methods to efficiently navigate the CIF data model. Examples of the use of the library will illustrate how CIFLIB has been applied as a data validation tool in processing crystal structure data at the Nucleic Acid Database Project.

Support for this work has been provided by the NSF (BIR 9510703).