On Fri, Nov 24, 2017 at 11:22:56AM +0800, 尹剑虹 wrote:
> It's not the point. the problem is bash-4.4 auto add quote around $var or
> $(cmd) after '<<<'
>
> On bash-4.2 and before following command always works fine
> read ignore fstype <<<$(df --output=fstype $mountpoint)
>
> But after Update bash-4.4, our customer's script get fail, do you understand
> what I mean?
The script is broken. It happened to work in bash 4.2 because of a bug
in bash 4.2 that cancelled out the bug in the script.
wooledg:~$ df --output=fstype /
Type
ext4
Here is how the script should be written:
{ read; read -r fstype; } < <(df --output=fstype "$mountpoint")
And testing it:
wooledg:~$ mountpoint=/
wooledg:~$ { read; read -r fstype; } < <(df --output=fstype "$mountpoint")
wooledg:~$ declare -p fstype
declare -- fstype="ext4"
