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                                                            traceback(3C)



        _________________________________________________________________
        traceback                                                function
        Print a stack traceback and continue.
        _________________________________________________________________


        Calling Sequence

        error = traceback(err);


          where   err is either a system error code, or 0 to use the
                  last error code.



        Description

        The traceback function prints a stack traceback on an error code,
        and then execution continues.  A stack traceback is a listing of
        each procedure previously performed, with the offset of each.  If
        you used the /LINEID switch on the compilation command line, the
        traceback will also tell you the line number in the source file
        of each procedure.


        Returns

        The traceback function returns the error code that is used.


        Related Functions

        The traceback function has no related functions.


        Example

        #include <stdio.h>

        main() {
            printf("Calling sec1.\n");
            sec1();
        }

        sec1()
        {
            printf("Calling sec2.\n");
            sec2();
        }




        DG/UX 4.00                                                 Page 1
               Licensed material--property of copyright holder(s)





                                                            traceback(3C)



        sec2()
        {
            printf("Calling sec3.\n");
            sec3();
        }

        sec3()
        {
            int   ch;
            while ((ch = getchar()) != EOF)
                putchar(ch);
            traceback(0);
            /* Print traceback & End of File error */
        }

        If you call the program test and enter

        abc

        you generate

        Calling sec1.
        Calling sec2.
        Calling sec3.
        abc

        ERROR 24.
        from $traceback.

        Call Traceback:

        from fp=16000013030, pc=sec3+161, line 663 of sec3
        from fp=16000012776, pc=sec2+31, line 651 of sec2
        from fp=16000012744, pc=sec1+31, line 643 of sec1
        from fp=16000012712, pc=main+31, line 635 of main
        from fp=16000012560, pc=.MAIN.+73, C initializer
        from fp= 0, pc=I.INIT+46

        END OF FILE

        These results will vary with execution.













        DG/UX 4.00                                                 Page 2
               Licensed material--property of copyright holder(s)



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