check installed cudnn version code example
Example 1: cudnn version linux
cat /usr/local/cuda/include/cudnn.h | grep CUDNN_MAJOR -A 2orcat /usr/include/cudnn.h | grep CUDNN_MAJOR -A 2
Example 2: find cudnn version
cat /usr/local/cuda/include/cudnn.h | grep CUDNN_MAJOR -A 2
#or :
cat /usr/include/cudnn.h | grep CUDNN_MAJOR -A 2