[gi] implement out arg handling

1 files changed, 13 insertions, 0 deletions

diff --git a/gi/pygi-invoke-state-struct.h b/gi/pygi-invoke-state-struct.h
index 1c9bf3e6..22ac8ea9 100644
--- a/gi/pygi-invoke-state-struct.h
+++ b/gi/pygi-invoke-state-struct.h
@@ -14,7 +14,20 @@ typedef struct _PyGIInvokeState
 
     GIArgument **args;
     GIArgument *in_args;
+
+    /* Out args and out values
+     * In order to pass a parameter and get something back out in C
+     * we need to pass a pointer to the value, e.g.
+     *    int *out_integer;
+     *
+     * so while out_args == out_integer, out_value == *out_integer
+     * or in other words out_args = &out_values
+     *
+     * We do all of our processing on out_values but we pass out_args to 
+     * the actual function.
+     */
     GIArgument *out_args;
+    GIArgument *out_values;
 
     GIArgument return_arg;