NAME
        log_file() - append a message to a log file

SYNOPSIS
        int log_file(string file, string message)

    
DESCRIPTION
        Append a message to a log file.  The log directory is to be
        specified in the runtime configuration file.  The log
        directory is automatically prepended to the filename. The 
	message is automatically prepended with time and date. If the
	same message is repated several times, it will only log the
	number of repetitions. The function returns 1 on success.

	If the logfile is over 200k it will be backed up, and a new
	logfile started up from fresh.

	This is an sfun and might not be available. This_object()
	will need write access to the logfile.

SEE ALSO
	efun/write_file