Subj : Re: void interrupt(*oldvects[2])(...); can't compile.
To   : borland.public.cpp.borlandcpp
From : Ed Mulroy [TeamB]
Date : Wed Dec 08 2004 10:39 am

The code you show appears to be from Serial.CPP, part of a
Borland tech info document on serial communications for
Turbo C++ for DOS from around 1989.

> 1. I do not recognize the declaration syntax [what does
> the (...) mean?
> 2. When trying to compile I get several errors, including:
>   E2449 Size of 'interrupt' is unknown or zero
>   E2141 Declaration syntax error at line 29 (the function
> itself)

In C and C++ an ellipsis (the three periods) indicate a variable
argument list.

The word 'interrupt' is a keyword specific to the compiler.  It
tells the compiler that the function is set up a specific way,
a way that is compatible with being called in response to
a processor interrupt.  In later years the language specifications
were changed and keywords specific to a given vendor are
suppossed to begin with an underscore so later compilers
used _interrupt.  Later still the language committees
required two instead of one leading underscores, making the
keyword __interrupt.  For backward compatability, unless
the ANSI standard option is enabled, all of interrupt,
_interrupt and __interrupt should be recognized by the compiler.

What compiler are you using?

You posted your question both here and in the C++ Builder X
group.  It is possible that you are trying to write a program for
Windows.  If so, this is 16 bit DOS code and will not work with
Windows.

..  Ed

> Nathan Witemberg wrote in message
> news:41b6a585@newsgroups.borland.com...
>
> I am having trouble with a serial communication routine (which
> I didn't write). Specifically with the interrupt handling routine
> which is the following:
>
> void interrupt com_int(void)
>   /* Handle communications interrupts and put them in ccbuf */
>   {
>    disable();
>    if ((inportb(portbase + IIR) & RX_MASK) == RX_ID)
>    {
>      ccbuf[endbuf++] = inportb(portbase + RXR);
>      endbuf %= SBUFSIZ;
>    }
>    /* Signal end of hardware interrupt */
>    outportb(ICR, EOI);
>    enable();
>
>   } /* com_int */
>
> Which is previously declared in an include file as:
> void  interrupt(*oldvects[2]) (...);
>
> 1. I do not recognize the declaration syntax [what does
> the (...) mean?
> 2. When trying to compile I get several errors, including:
>   E2449 Size of 'interrupt' is unknown or zero
>   E2141 Declaration syntax error at line 29 (the function
> itself)
>
> I have seen that this is a rather common routine, anybody
> with experience in serial cummunication? Any clue as how
> to get past the compile errors?

.