On Dec 18, 2006, at 4:32 PM, Jim Dossey wrote:
I have a question about using ByRef in Declares and Function calls.
Say I need to call an OS function using a Declare, and that
function needs a
pointer to a 4 byte integer in order to return some value. I would
call
this function like this:
Dim i As Integer
Declare Sub SomeFunc Lib "somelib" (ByRef Data As Integer)
SomeFunc(i)
The returned value is now in 'i'.
But what happens when this code is in a subroutine that I need to
call, and
pass in the integer pointer? Now that code looks ike this:
Sub MyFunc (ByRef i As Integer)
Declare Sub SomeFunc Lib "somelib" (ByRef Data As Integer)
SomeFunc(i)
End Sub
and I call this using
Dim x As Integer
MyFunc(x)
Now I'm using ByRef twice. So when I call SomeFunc am I going to
pass a
pointer to a pointer to 'x'?
_______________________________________________
Probably. But why would you define a subroutine that takes a
parameter by reference?
Charles Yeomans
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