What is the difference between a venu and a bansuri?

The venu of Carnatic music has eight finger holes, with Sa fingered on the first two holes closed. The Hindustani bansuri has six finger holes in line with the blow hole, and Britannica describes six or seven. On the venu the eighth hole stays open except in special fingerings that cover all eight; the Horniman Museum lists it on one venu as a tuning hole.