NAME

       VistaIOSetErrorHandler - register a procedure to be called on any fatal error

SYNOPSIS

       void VistaIOSetErrorHandler (VistaIOErrorHandler *handler);

       typedef void VistaIOErrorHandler (VistaIOStringConst message);

       void VistaIODefaultError (VistaIOStringConst message);

ARGUMENTS

       handler   Specifies the new fatal error handler.

       message   Specifies a null-terminated error message string to be reported.

DESCRIPTION

       VistaIOSetErrorHandler  registers  a  procedure, handler, as the fatal error handler. That
       procedure is called by VistaIOError(3) or by VistaIOSystemError(3)  to  report  any  fatal
       error.  When  called,  it is passed a string, message, containing a textual description of
       the error.

       Only one procedure serves as the fatal error handler at any one time.

       Prior to the first call to VistaIOSetErrorHandler, the  procedure  VistaIODefaultError  is
       the fatal error handler. This procedure will write the error message to the standard error
       stream, then terminate  the  program  by  calling  exit(3)  with  a  status  value  of  1.
       VistaIODefaultError  can  be  re-established  as  the  fatal  error handler at any time by
       calling VistaIOSetErrorHandler with a NULL argument.

RETURN VALUES

       A fatal error handler should never return.

EXAMPLES

       To adopt an error handler that writes messages both to the standard error stream and to  a
       log file, one might do the following:

              FILE *log_file;

              void MyErrorHandler (message)
                   VistaIOStringConst message;
              {
                   fputs (message, stderr);
                   fputs (message, log_file);
                   exit (1);
              }

              int main (...)
              {
                   ...
                   log_file = fopen ("log", "w");
                   VistaIOSetErrorHandler (MyErrorHandler);
                   ...
              }

SEE ALSO

       VistaIOError(3), VistaIOSetWarningHandler(3),

AUTHOR

       Art Pope <pope@cs.ubc.ca>

       Adaption to vistaio: Gert Wollny <gw.fossdev@gmail.com>