bash - Print unicode character

Question

With Bash, you can use printf with hex codes

xHH   byte with hexadecimal value HH (1 to 2 digits)
uHHHH Unicode (ISO/IEC 10646) character with hex value HHHH (4 digits)

example

$ printf 'x26'
&

However the Unicode example does not print as expected

$ printf 'u0026'
u0026

My Bash version

$ echo $BASH_VERSION
4.1.10(4)-release

Answer 1

What version of bash are you using (echo $BASH_VERSION or bash --version)? The Unicode escapes work in bash 4.2, but not 3.2.48. I suspect support was added in bash 4.0.

Update: I can confirm it does not work in bash 4.1.2. This functionality appears to have been added in bash 4.2.

Update 2: From the release notes for bash 4.2:

d. $'...', echo, and printf understand uXXXX and UXXXXXXXX escape sequences.