How do you echo a 4-digit Unicode character in Bash?

I'd like to add the Unicode skull and crossbones to my shell prompt (specifically the 'SKULL AND CROSSBONES' (U+2620)), but I can't figure out the magic incantation to make echo spit it, or any other, 4-digit Unicode character. Two-digit one's are easy. For example, echo -e "\x55", .

In addition to the answers below it should be noted that, obviously, your terminal needs to support Unicode for the output to be what you expect. gnome-terminal does a good job of this, but it isn't necessarily turned on by default.

On macOS's Terminal app Go to Preferences-> Encodings and choose Unicode (UTF-8).

In UTF-8 it's actually 6 digits (or 3 bytes).

$ printf '\xE2\x98\xA0'
☠

To check how it's encoded by the console, use hexdump:

$ printf ☠ | hexdump
0000000 98e2 00a0                              
0000003

% echo -e '\u2620'     # \u takes four hexadecimal digits
☠
% echo -e '\U0001f602' # \U takes eight hexadecimal digits
😂

This works in Zsh (I've checked version 4.3) and in Bash 4.2 or newer.

So long as your text-editors can cope with Unicode (presumably encoded in UTF-8) you can enter the Unicode code-point directly.

For instance, in the Vim text-editor you would enter insert mode and press Ctrl + V + U and then the code-point number as a 4-digit hexadecimal number (pad with zeros if necessary). So you would type Ctrl + V + U 2 6 2 0. See: What is the easiest way to insert Unicode characters into a document?

At a terminal running Bash you would type CTRL+SHIFT+U and type in the hexadecimal code-point of the character you want. During input your cursor should show an underlined u. The first non-digit you type ends input, and renders the character. So you could be able to print U+2620 in Bash using the following:

echo CTRL+SHIFT+U2620ENTERENTER

(The first enter ends Unicode input, and the second runs the echo command.)

Credit: Ask Ubuntu SE