Use a separate history for 'read -e' (readline)

Question

I would like to write an interactive command shell in shell script, for easier adjusting of the iptables firewall. The problem is, that read -e uses the shell history. Is there a way of using a separate history for read -e in a script?

Answer 1

If you have rlwrap (debian package rlwrap), then you could use something like:

LINE=$(rlwrap head -n1)

which will use the file ~/.head_history by default. (man rlwrap for more details, including options for specifying a history filename.)

Another possibility is to run read in a subshell with HISTFILE set to your own history file, but you'll need to do a lot more work because although read -e uses the history, it does not update it. So you'll probably need something like:

LINE=$(bash -c 'HISTFILE=/path/to/history_file;
                history -r; read -e LINE;
                history -s "$LINE"; history -w;
                echo "$LINE"')