Related Syntax		Other Library Functions

Library: builtins - functions for logging Include: builtins.xin

Declaration

  define external function log-message
              value stream message-text
        class value stream class-value optional initial {""}
     severity value integer severity-value optional initial {0}
     as log_message in function-library #builtin

This function is meant to be used as a general mechanism for error and status logging.

log-message receives the error or status message and passes to it to whatever "-log" stream is bound to. If it is bound to "mylog.log", that file will receive the error or status message. This means that when you run your OmniMark program, log-message sends messages to mylog.log, while writing to #error sends text to standard error.

You can set the destination of log-message:

• on the command line, you included "-log mylog.log", or
• in the IDE, you specified "-log mylog.log" in the "Extra" tab of Project Options, under the Edit menu.

Note: You can also specify "-alog mylog.log" from the command line if you wish to append all log messages to the same file rather than overwriting the previous contents of the file each time there is a message.

log-message is useful in batch environments, both because it gives access to the "-log" stream, and because it is invoked in a uniform manner in a server environment. It is useful in server environments because it provides a consistent interface to what can be a variety of message processing systems.

Arguments:

• message-text -- the text of the message.
• severity-value -- this is an integer value that indicates the severity or class of the logged message. Note that this is only used for the OmniMark Interpreter with network logging. Unless otherwise defined, the log message routines will display the following values:
  • 0 as "WARNING"
  • 1 as "ERROR" (recoverable)
  • 2 as "SEVERE ERROR" (non-recoverable)
  • 3 as "INTERNAL ERROR"
• class-value -- the text of a user-defined category in which to place the logged message.