Help! function declare.

[Raymond]

Hello All:
I have find a function declaration like following:

------------------------------------------------
extern int _ts_callback_abort _((GTRID *, long));
------------------------------------------------
What's the meaning of this statement?

Thank you
Raymond shen.

[T.M. Sommers]

Raymond wrote:

Hello All:
I have find a function declaration like following:

------------------------------------------------
extern int _ts_callback_abort _((GTRID *, long));
------------------------------------------------
What's the meaning of this statement?

_ will be a macro. Find where it is defined and all should be clear.

--
Thomas M. Sommers -- tm*@nj.net -- AB2SB

[August Karlstrom]

Raymond wrote:

Hello All:
I have find a function declaration like following:

------------------------------------------------
extern int _ts_callback_abort _((GTRID *, long));
------------------------------------------------
What's the meaning of this statement?

`_' must be a macro function

#define _(x) ...

called with argument `(GTRID *, long)'. Without its definition it's hard
to say what happens.
-- August

[Martin Ambuhl]

Raymond wrote:

Hello All:
I have find a function declaration like following:

------------------------------------------------
extern int _ts_callback_abort _((GTRID *, long));
------------------------------------------------
What's the meaning of this statement?

First, you need to find out what the macro _() is.
That macro has no standard meaning, so it should be available in the
included non-standard headers. Of course, we can all guess what it is:
a macro designed to make the declaration work whether the implementation
can handle prototypes or not. This sort of hack should disappear soon,
since it has been 16 years since the C standard mandated that prototypes
be supported.

So, assume that _(x) expands to x
We now have
extern int _ts_callback_abort (GTRID *, long);

This is the declaration for an implementation-specific function which is
part of the implementation, since no one else can use such a name for a
function. It takes two arguments, one a pointer to a variable of an
unknown non-standard type GTRID, the other a long. That makes *two*
needed definitions you failed to give us (the macro _() and the type
GTRID). The function returns an int, and has external linkage.

[pete]

Raymond wrote:

Hello All:
I have find a function declaration like following:

------------------------------------------------
extern int _ts_callback_abort _((GTRID *, long));
------------------------------------------------
What's the meaning of this statement?

That's a declaration.
Declarations and statements are two dfifferent things.
The body of a C89 function definition contains
declarations followed by statements.
A translation unit consists of external declarations.

--
pete