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>