[Pyrex] using C char array problem

[Helmut Jarausch]

On 23 May, Eric Colleu wrote:
> Hi,
> 
> I have a problem with pyrex array management.
> I define a type
> ctypedef char machaine[10]
> And I try to pass an array of this type to a C function with no success.
> Below is my C code and pyrex code.
> Please help me or I'm gonna be crazy...
> 

For Pyrex there is no difference between a
char* variable and a machaine type variable.

> cdef extern from "apienc.h":
>          ctypedef char machaine[10]

replace this with a simple
           ctypedef char* machaine

>          void testDeTableauDeString(machaine *montableau, int nbelt)
> 
> def testapi(stringlist):
>          cdef machaine *myarray
>          cdef machaine *p[10]

>          cdef int buflen
>          for i, s in enumerate(stringlist):
>                  print "Value of s : " +  s
>                  PyObject_AsReadBuffer(s, <void **>&myarray, &buflen)
>                  p[i] = myarray
>                  print "buflen =", buflen
>                  print "Value of myarray : %s" % 
> PyString_FromStringAndSize(<char *>myarray, buflen)
>                  print "Value of p : %s" % PyString_FromStringAndSize(<char 
> *>p[i], buflen)
>          testDeTableauDeString(p[0], len(stringlist))

In C (not C++) the linkage for a function with a char* parameter
and a corresponding one with a  machaine type parameter is the
same. So, nobody will notice the difference.
The difference shows up only when you compile the C-source of any
functions taking a machaine type parameter.

-- 
Helmut Jarausch

Lehrstuhl fuer Numerische Mathematik
RWTH - Aachen University
D 52056 Aachen, Germany