Looking for a quick way to convert your hexadecimal piece to decimal? Other way around?
Just a simple
$ printf '%d' 0xCAFE # Output: 51966
And a DEC to HEX conversion is possible with
$ printf '%x' 51966 # Output: cafe
You can also use an inline expression with double parenthesis in order to get the decimal value and use it at your will
$ $((0xCAFE)) zsh: command not found: 51966
This will try to execute a command named 51966 which will generally duh fail..
Examples with printf assume that you have a POSIX Compliant Shell
You can read the man page for printf(1) to learn other printf options.