How to change ROI after imgSessionConfigure

[Harold Bien]

Here's an interesting behavior I noted with IMAQ v3.1.3:

1) Open an interface and session
2) Use CreateBufList and CreateBuffer to make a simple, 1 element buffer list
3) Attach the buffer list to the session using imgSessionConfigure()
4) Now, attempt to change the IMG_ATTR_ROI or IMG_ATTR_ACQWINDOW using imgSetAttribute or even imgSessionSetROI

There are no errors generated from this process, but if you perform a subsequent imgGetAttribute for ROI or ACQWINDOW, you will find that they did not change from the original values. It appears as if calling imgSessionConfigure() locks the ROI/ACQWINDOW.

My question is thus: how do you go about "unlocking" the ROI and ACQWINDOW? Must I close and re-open a new session?

(BTW, in the 'LLgrab.c' example they use a function "imgMemLock()" that I was not able to find in the documentation. Perhaps
imgSessionConfigure() calls similar functions, and maybe there is another undocumented function that would provide the corresponding "unlock" function?)

Thanks.

[Harold Bien]

A little bit of personal testing seemed to indicate that a call to imgMemUnlock(BUFFLIST_ID bid) did the trick. I was able to re-configure the ROI/ACQ_WINDOW attributes after unlocking the memory that was locked by imgSessionConfigure().