// how do I pass the variable arguments to Perl?

You should be able to do what you want by making use of items, which is set to the number of arguments being passed: 
use strict;
use warnings;

use Inline C => Config =>
    BUILD_NOISY => 1;

use Inline C => <<'EOC';

void foo(SV * a, ...) {
     dXSARGS;
     int i, t;

/* add new values onto the end of the stack */
     for(i = 0; i < items; i++) {
         t = SvIV(ST(i)) * 3;
         XPUSHs(newSViv(t));
        }

     for(i = 0; i < items * 2; i++) {
        printf("%d\n", SvIV(ST(i)));
        }
}

void bar(SV * a, ...) {
     dXSARGS;
     int i, t;

/* overwrite the existing stack values 
   with new ones */

     sp =  mark;

     for(i = 0; i < items; i++) {
         t = SvIV(ST(i)) * 3;
         XPUSHs(newSViv(t));
        }

     for(i = 0; i < items; i++) {
        printf("%d\n", SvIV(ST(i)));
        }
}

EOC

foo(1 .. 5);
print "\n";
bar(1 .. 4);

[download]
Cheers,
Rob

In reply to Re: calling from C - variable argument list by syphilis
in thread calling from C - variable argument list by marksman

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