What is the use of "&>>" in bash?

Question

I was studying a bash script code where I encountered operator "&>>". I didn't understand its use. So, I referred to http://www.gnu.org/software/bash/manual/html_node/Redirections.html .

It is semantically equivalent to >> file 2>&1 .

Following is the output from my shell :-

# echo $SHELL
/bin/bash
# echo "hello" &>> file1
bash: syntax error near unexpected token `>'

and

# echo "hello" >> file1 2>&1

# cat file1 

hello

Question :- Why am I getting error bash: syntax error near unexpected token '>' ?

[EDIT] :- Bash version 3.2.25(1)-release (x86_64-redhat-linux-gnu)

Answer 1

You are getting that error because you using an older version of bash (3.2.25).

Since Bash4, there's &>>TARGET, which is equivalent to >> TARGET 2>&1.

Source: Appending redirected output

So, you should take in consideration an upgrade. I use bash version 4.2.45 and echo "hello" &>> file1 works like a charm for me.

Answer 2

This feature was introduced in bash 4.0 alpha, so it should be available in any bash >= 4.0.

http://git.savannah.gnu.org/cgit/bash.git/tree/CHANGES?id=0001803f0b9523c94fa2ede48eaecb047fef4524 -- line 976.

(The original 4.0-alpha changelog mis-reported the operator as >>&. The man page shows the correct &>>, and the typo was corrected in 4.1.)