error.c

Intro/: Directory containing introductory examples. HelloWorld.c A simple program that draws a bo

#include <phigs.h>			/* get HP-PHIGS definitions for C */
#include <stdio.h>			/* get standard I/O definitions */

main()					/* file "Error.c" */
{
    Pint	WorkstnID = 1;		/* workstation identifier */
    Pint	ConnID;			/* connection identifier */
    Pint	WorkstnType = POIDDX;	/* out/in, direct, dbl bfr, Xwindow */
    static Plimit BadLimits =		/* deliberately illegal values */
		{0.0, 0.0, 0.0, 0.0};
    Pint	ErrorRtn;		/* returned from "pescape_u700" */
    
    void	MyErrorHandler();	/* forward reference */
    void	(*OldHandler)();	/* pointer for previous handler */

    popen_phigs((char *) stderr, 0);	/* errors go to "stderr" */
    pescape_u4("/dev/screen/phigs_window", &ConnID);
    popen_ws(WorkstnID, (void *) ConnID, WorkstnType);
    /*--- make an error with the default error-handler in effect -----------*/
    printf("--- Default error-handler in effect -------------------------\n");
    pset_ws_win(WorkstnID, &BadLimits);
    /*--- turn off error handling completely -------------------------------*/
    printf("--- No error-handler in effect ------------------------------\n");
    pset_err_hand_mode(PERR_OFF);
    pset_ws_win(WorkstnID, &BadLimits);
    /*--- install custom error-handler and make error again ----------------*/
    printf("--- Custom error-handler in effect --------------------------\n");
    pset_err_hand_mode(PERR_ON);
    pset_err_hand(MyErrorHandler, &OldHandler);	/* replace handler */
    pset_ws_win(WorkstnID, &BadLimits);
    pclose_ws(WorkstnID);
    pclose_phigs();
}
/****************************************************************************/
void MyErrorHandler(ErrorNo, FuncID, ErrorFile)
int	*ErrorNo;			/* which error happened? */ 
int	*FuncID;			/* which routine had the error? */
void	*ErrorFile;			/* print error messages where? */
{
    printf("MyErrorHandler: Error %d occurred in routine %d.\n", *ErrorNo,
      *FuncID);
    printf("My own call to the ERROR LOGGING routine (perr_log):\n");
    perr_log(*ErrorNo, *FuncID, ErrorFile);
}