How to create an output buffer for GPIB communication using instrument's communication DLL

[SteveMcGill]

I am trying to communicate with an instrument which interfaces with its computer controller through GPIB. The instrument's software includes a DLL which allows one to write VIs, using LabVIEW's call library function, to communicate with the instrument apart from the manufacturer's proprietary software. My VI to send and read is crashing because I need to allocate an output buffer for the response. How do I do this? (LabVIEW 6.0.1, Windows 98)

[mikeporter]

given that there can be a variety of reasons for something to crash, you can sometimes initialize a buffer by wiring a non-null data structure to the left terminal of the call library function node. for example, if the output is to be a string no more than 100 characters long, create a string that long of nulls, blanks or anything and attach that to the left terminal for that output. no guarantees, but i have seen that work.