Re: SCM_CALL_N

[Lars J. Aas]

On Tue, Jun 26, 2001 at 12:36:04PM -0500, Rob Browning wrote:
: "Lars J. Aas" <address@hidden> writes:
: > Try making your own wrapper around printf() and see.  You can't -
: > you can only pretend you wrap printf() but actually forward the
: > invokation to vprintf().  That's probably why the vprintf() family
: > is there - so you can make your own variants that wrap the real
: > printf-implementation.  It's a moot point since it's only a problem
: > if you need to make wrapper functions, and you may not want to
: > invest any extra effort in libguile to support that.
: 
: Actually this is a good point.  The problem is that there's no
: portable (AFAIK) implementation of anything like "apply" for C given a
: varargs list.  You can't build an argument list and then call a normal
: varargs C function using that list.

That's true - you can not build the va_list yourself (without butting your
head up against the portability wall), but you can forward va_list objects,
and you can forward va_list objects after having read in (and thereby
discarding) the first N arguments.

  Lars J
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