Delphi WinWaitActive problem with null string for text

[mdavid]

I'm using v3 in Delphi. I get an access error when using a null string for text as in:

WinWaitActive("Login Dialog","",20)

but I don't get an access error if I replace the null string by a space as

WinWaitActive("Login Dialog"," ",20)

In autoit script mode neither of these statements gives an access error. Any idea what is going on?

[mdavid]

Well, I found the solution so here it is for anyone interested. In the Delphi wrapper for AutoITX, the strings are all type WideString and if s is a widestring, the null string should be initialized by s := '' + #0.

The #0 is necessary, but only for the null string.