gencat

gencat [-V] catalog_file msg_file...

catalog_file
    The path to the message catalog file to create or update. This file stores messages in a binary format, used by functions like catgets(3).

msg_file
    One or more input message source files. These files contain message definitions in a specific plain-text format, including set IDs, message IDs, and the actual message strings.

-V
    Displays version information for the gencat utility and then exits.

gencat is a standard utility specified by POSIX for creating and managing message catalogs used in internationalization (i18n). It takes one or more source files, typically with a .msg extension, containing locale-specific messages and merges them into a binary message catalog file, often named with a .cat extension. If the specified catalog_file does not exist, gencat creates it. If it already exists, new messages are merged with existing ones. Messages with matching set IDs and message IDs in the input msg_file will replace their counterparts in the existing catalog_file. This process allows applications to retrieve localized messages at runtime using functions like catgets(3), making software adaptable to various languages and regions without code changes. The input message files follow a specific format, defining message sets, individual messages, and optionally, a quote character.

The format of the msg_file is critical; incorrect syntax can lead to catalog generation errors. Messages in the catalog_file are stored in a binary format, meaning they are not directly human-readable or editable after generation. gencat is part of the POSIX internationalization framework, which is distinct from the more widely used GNU gettext system, though both serve similar purposes. Applications must use catgets(3) or similar POSIX functions to access messages from catalogs created by gencat.

Input message source files (.msg files) adhere to a specific format. Lines starting with `$` are directives or comments.

• `$set N`: Defines the current message set ID to N. Subsequent messages without a set directive belong to this set.
• `$delset N`: Deletes message set N from the catalog.
• `$quote C`: Defines C as the quote character for message strings, overriding the default `"`.
• `msgid message_string`: Defines a message with msgid in the current set. The message_string can be quoted.

gencat is a core utility specified by the X/Open Portability Guide (XPG) and later incorporated into the POSIX.1-2001 and POSIX.1-2008 standards for internationalization. It was developed as part of a standardized approach to allow applications to present locale-specific messages to users, facilitating software localization across different languages and regions. Its design is intrinsically linked with the catgets(3) function, forming a foundational mechanism for message retrieval in internationalized applications before the widespread adoption of other systems like GNU gettext.

catgets(3), mkmsgs(1), runcat(1), exstr(1)