PureBasic Forum

Hi all,

hope you can help me with a problem.
I have a dll where functions need some parameter a value as unsigned char.
Sample:


How i must call the dll function to send a unsigned char as parameter?

Thanks
Nico

Hi,

for your example you need no unsignged char, since it is a pointer.
So you need a *Ptr as parameter or an integer.

Bernd

unsigned char is 0 to 255, so use variable type of Ascii = .a

or as infratec pointed out, a POINTER of the variable, which is type Ascii.

With prototypes you should use p-ascii if the parameter is only [out], means you give
the buffer to the chars, but you don't receive something from it (p-ascii does not
translate back the return buffer after the function call).


Without using prototype with p-ascii:

In ASCII mode you can just give the address to a string: @"my string"

In Unicode mode you have to convert the string to ASCII first and give the address to that buffer.

If you get something returned in the buffer, you give the address of a (string)buffer. buffer.s = Space(length) -> give @buffer to the function.
In Unicode mode you do buffer.s = PeekS(@buffer,-1,#PB_Ascii) to get the ASCII string after the function returned.

With prototypes:Bernd

see ==> pseudotypes in purebasic help:

Of course. The separated lines were other ways, without using prototypes and p-ascii.
Sorry, i did not make this clear enough.

Thank you Danilo,

for your kind answer!

I read it too fast! If I read your text more carefully, I would have understand it!
Both lines refer to the previous line: "Without using prototype with p-ascii:"

I misunderstood it!

guido

Here *input.a should be *input.Ascii or merely *input as qualifying pointers as native types does nothing and leads to confusion. The compiler should disallow it imho but it lets it go.

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