----- Original Message ----- 
From: "Greg McKaskle" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Monday, June 07, 2004 5:08 PM
Subject: Re: Call Library


> If you need the return value to work, you will want to get it as a four
> by integer.  You won't be able to get it into a string without making
> another call to dereference the pointer, interpret it as a string, and
> copy the contents into a LV string.

Well, it does work as-is once I decided to try sending it version numbers to
check against. And once I realised it was 0.3.6 instead of something >1 and
quit sending "1.0.0" as my test string :)

There's a similar case of returning a string directly in the error reporting
function of the VIs that interface with the Comedi library, which is what
persuaded me to keep hammering at it.

> As Jason pointed out, LV doesn't pass empty strings as NULL.  If you
> want to pass NULL, build another signature passing the pointer as an
> integer and pass a zero.

Thanks to both- that's something I'll try when I get a bit more time to
spare.




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