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Hi there, forgive me for asking a really basic question; I tried my best without getting anywhere with Perl XS, and I'm hoping someone could help me out on this.

I basically tried to pass an array by reference to my C subroutine that takes a pointer to a double. Here's the c code and header I have:

========my c file======
#include "myfunction.h" double do_nothing(double *para) { return para[0]; }
====end of c file=====
===my header file ===
double do_nothing(double *)
===end of header file==
===my xs file =======
#include "myfunction.h" (and the rest of the XSUB header files) MODULE = Myfunction PACKAGE = Myfunction PROTOTYPES: ENABLE double do_nothing(x) double * x
===============end of my xs file ======
=============my local typemap file============
double * T_SV
=============end of typemap file=============

when I ran "make" it seemed fine. but when I tried to test my code by including the following command in my test file:

my @array = (1.1,1.2); is(&myfunction::do_nothing(\@array),1.1);
it failed, saying:

got: '4.56890170385568e-317',
expected: '1.1'

What did I do wrong here? many thanks in advance!

In reply to perl xs pass an array by reference by andromedia33

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