UFFI-izing varargs


While trying to write a (working) interface to the syslog
family of C functions I came across the varargs problem:

The C function is defined as:

void syslog( int priority, const char *messae, ...)

Hm - how to transform this into a suitable UFFI definition
and how to call it then ?

I have so far:

###

;; FUNCTION DEFINITION

(uffi:def-function ("syslog" _syslog)
((priority :int)
(message :cstring))
:returning :void)

;; SYSLOG: CALLING THE C FUNCTION

(defun syslog (priority message &rest args)

(declare (ignorable args))

;; write message to syslog

(with-cstring (c-message message)
(_syslog priority c-message))
)

###

That's obviously only half of the thing I want. So,
my questions are:

1. How to deal with the &rest args ?
Is this the right approach ?

2. How to call `format' to transform the args into one
string which can then be passed to syslog ?

I see that using approach 2) properly there's no need
for a varargs definition any more. So, 2) means how to
loop ober the args ... Oh, wait, that should be easy ;-)
It once again shows that I am still a newbie.

Thanks for any input and feedback.

Frank

--
Frank, the Ham DG1SBG
.

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