LOGWRITE(3A)                                         LOGWRITE(3A)



  NAME
       LogWrite, LogSystemError, LogDebug, LogAssert - write a
       message to the log file


  SYNOPSIS
       #include <Atari/log.h>

       LogWrite (fmt, arg ...)
       char *fmt;

       LogSystemError (fmt, arg ...)
       char *fmt;

       LogDebug (level,(fmt, arg ...))

       LogAssert (level,condition,(fmt, arg ...))

  DESCRIPTION
       LogWrite writes the string to the log file.  It processes a
       printf(3)-style format string with arguments.  It tries to
       put the date and time at the beginning of each line.  It
       uses the last character in the format string to decide if it
       has reached the end of a line or not, so if the format
       string ends in ""%s"", a newline could be emitted that would
       not be detected by LogWrite.

       LogSystemError reports a system error, the type that sets
       the global variable errno.  Unlike perror(3), this accepts
       printf-style arguments.  If previous calls to LogWrite have
       not produced an end of line, one is added.  Then the date
       and time are emitted, followed by the formatted text.  The
       text should not contain a new line, since it is followed by
       a colon, then the standard system error message, such as
       that presented by perror.  The message is terminated with a
       period and newline.

       LogDebug is a macro defined in the include file
       <Atari/log.h>. It checks level against the constant
       LOGLEVEL, and if the level is less than or equal to


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  LOGWRITE(3A)                                         LOGWRITE(3A)



       LOGLEVEL, generates a call to LogWrite.  If the level is
       greater than LOGLEVEL, no code is generated at all.  Thus,
       one can place debug messages in code at various level, and
       only those requested by LOGLEVEL will be compiled in.  In
       <Atari/log.h>, LOGLEVEL is set to zero if not already
       defined.

       Note that there is an extra set of parentheses to the
       parameters to LogWrite, since traditional cpp's cannot
       handle a variable number of parameters in their macros.

       LogAssert macros tests an assertion.  If level is less than
       or equal to the current LOGLEVEL, it tests the given
       condition.  If the condition is false, it makes a call to
       LogWrite.  As with LogDebug, this macro has extra
       parentheses around the printf-style arguments.

  SEE ALSO
       LogOpen(3A)























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