object: use fopen on windows

on Windows, fdopen is broken.
use fopen instead.

Fixes #21.

Author: sbinet

object.go

@@ -91,16 +91,6 @@ func int2err(i C.int) error {
 	return &gopy_err{fmt.Sprintf("error in C-Python (rc=%i)", int(i))}
 }
 
-// file2py opens a stdC file from a Go os.File.  Note the returned file has
-// been newly opened: the caller must close it with C.fclose(retval).
-func file2py(f *os.File, mode string) *C.FILE {
-	cmode := C.CString(mode)
-	defer C.free(unsafe.Pointer(cmode))
-	fd := f.Fd()
-	file := C.fdopen(C.int(fd), cmode)
-	return file
-}
-
 func file2go(f *C.FILE) *os.File {
 	return nil
 }

object_posix.go

@@ -0,0 +1,21 @@
+package python
+
+//#include <stdlib.h>
+//#include <string.h>
+//#include <stdio.h>
+import "C"
+
+import (
+	"os"
+	"unsafe"
+)
+
+// file2py opens a stdC file from a Go os.File.  Note the returned file has
+// been newly opened: the caller must close it with C.fclose(retval).
+func file2py(f *os.File, mode string) *C.FILE {
+	cmode := C.CString(mode)
+	defer C.free(unsafe.Pointer(cmode))
+	fd := f.Fd()
+	file := C.fdopen(C.int(fd), cmode)
+	return file
+}

object_windows.go

@@ -0,0 +1,22 @@
+package python
+
+//#include <stdlib.h>
+//#include <string.h>
+//#include <stdio.h>
+import "C"
+
+import (
+	"os"
+	"unsafe"
+)
+
+// file2py opens a stdC file from a Go os.File.  Note the returned file has
+// been newly opened: the caller must close it with C.fclose(retval).
+func file2py(f *os.File, mode string) *C.FILE {
+	cmode := C.CString(mode)
+	defer C.free(unsafe.Pointer(cmode))
+	name := C.CString(file.Name())
+	defer C.free(unsafe.Pointer(name))
+	file := C.fopen(name, cmode)
+	return file
+}