How do I compute the double sha256 shown in example of bip 143?
hashPrevouts:
dSHA256(fff7f7881a8099afa6940d42d1e7f6362bec38171ea3edf433541db4e4ad969f00000000ef51e1b804cc89d182d279655c3aa89e815b1b309fe287d9b2b55d57b90ec68a01000000)
= 96b827c8483d4e9b96712b6713a7b68d6e8003a781feba36c31143470b4efd37
I tried
export PREV_OUT=fff7f7881a8099afa6940d42d1e7f6362bec38171ea3edf433541db4e4ad969f00000000ef51e1b804cc89d182d279655c3aa89e815b1b309fe287d9b2b55d57b90ec68a01000000
echo -n $PREV_OUT |openssl dgst -sha256 -binary |openssl dgst -sha256
This is what I am getting
cf4cff3b2196ae87636af6088736f0f9102106375f306c032804845a2d3b92d4