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];
}

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====end of c file=====
===my header file === 
double do_nothing(double *)

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===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

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===============end of my xs file ======
=============my local typemap file============ 
double * T_SV

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=============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);

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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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