Question

How do I convert a hex strign to its 32 bit signed int equivalent in ruby?
for example

a = "fb6d8cf1" #hex string
[a].pack('H*').unpack('l') #from the documentation it unpacks to its 32 bit signed int

It converts to

-242455045

But the actual answer is

-76706575 

Could you point me to what I am doing wrong?

Answer 1

You could flip the bytes yourself to get around the endian and sign issues:

>> ['fb6d8cf1'.scan(/[0-9a-f]{2}/i).reverse.join].pack('H*').unpack('l')
=> [-76706575]