One of the requirements for internationalization of programs is that messages be displayed in the language of the user. This requirement is satisfied by producing versions of the messages which are translated into all supported languages.
The OS2 C library messaging support is based on the messaging support described in the X/Open XPG4 specification. It consists of functions for extracting messages from message catalog files (catopen, catgets, catclose) and utilities for producing message catalog files (gencat, mkcatdef). The functions are documented in the C Library Reference and the utilities are documented in this book.
The Generate Message Catalog Utility (GENCAT) creates and modifies a message catalog. GENCAT creates the message catalog (usually *.cat) from a message text source file (usually *.msg) or standard input.
If a message catalog with the name specified by the CatalogFile parameter exists, GENCAT modifies it according to the statements in the specified message source files. If the message catalog does not exist, GENCAT creates a catalog file with the name specified by the CatalogFile parameter.
You can specify any number of message source files. GENCAT processes multiple source files, one after another, in the sequence specified. Each successive source file modifies the catalog. If you do not specify a source file, GENCAT accepts message source data from standard input.
GENCAT does not accept symbolic message identifiers. You must run MKCATDEF if you want to use symbolic message identifiers in your message source file (see Preprocess Message Source File Utility (MKCATDEF)).