Manual Pages for UNIX Operating System command usage for man vlfmt

Standard C Library Functions                            vlfmt(3C)



NAME
     vlfmt - display error message in standard format and pass to
     logging and monitoring services

SYNOPSIS
     #include 
     #include 

     int vlfmt(FILE *stream, long flag, const char *format, va_list ap);


DESCRIPTION
     The vlfmt() function is identical to lfmt(3C),  except  that
     it is called with an argument list as defined by .


     The  header defines the type va_list and a set  of
     macros  for  advancing  through  a  list  of arguments whose
     number and types may  vary.  The  ap  argument  is  of  type
     va_list.  This  argument  is used with the  macros
     va_start(), va_arg(), and va_end().  See  stdarg(3EXT).  The
     example in the EXAMPLES section below demonstrates their use
     with vlfmt().

RETURN VALUES
     Upon successful completion, vlfmt() returns  the  number  of
     bytes transmitted.  Otherwise, -1 is returned if there was a
     write error to stream, or -2 is returned if  unable  to  log
     and/or display at console.

EXAMPLES
     Example 1 Use of vlfmt() to write an errlog()routine.


     The following example demonstrates how vlfmt() could be used
     to  write  an errlog() routine. The va_alist() macro is used
     as  the  parameter  list  in  a  function  definition.   The
     va_start(ap, ...) call, where ap is of type va_list, must be
     invoked before any attempt to traverse  and  access  unnamed
     arguments.  Calls to va_arg(ap, atype) traverse the argument
     list. Each execution of va_arg() expands  to  an  expression
     with the value and type of the next argument in the list ap,
     which is the same  object  initialized  by  va_start().  The
     atype  argument  is  the  type that the returned argument is
     expected to be. The va_end(ap) macro must  be  invoked  when
     all  desired arguments have been accessed. The argument list
     in ap can be traversed again if va_start() is  called  again
     after  va_end().) In the example below, va_arg() is executed
     first to retrieve the format string passed to errlog().  The
     remaining errlog() arguments (arg1, arg2, ...) are passed to
     vlfmt() in the argument ap.




SunOS 5.11          Last change: 29 Dec 1996                    1






Standard C Library Functions                            vlfmt(3C)



       #include 
       #include 
       /*
        *   errlog should be called like
        *         errlog(log_info, format, arg1, ...);
        */
       void errlog(long log_info, ...)
       {
               va_list ap;
               char *format;
               va_start(ap, );
               format = va_arg(ap, char *);
               (void) vlfmt(stderr, log_info|MM_ERROR, format, ap);
               va_end(ap);
               (void) abort();
       }


USAGE
     Since  vlfmt()  uses  gettxt(3C),  it  is  recommended  that
     vlfmt() not be used.

ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | MT-Level                    | MT-Safe                     |
    |_____________________________|_____________________________|


SEE ALSO
     gettxt(3C), lfmt(3C), attributes(5), stdarg(3EXT)


















SunOS 5.11          Last change: 29 Dec 1996                    2