is there a way to export bash shell options to subshell?

Question

I set bash options (e.g. shopt -e autocd) in current shell & want to export/copy this options to a newly created subshell. Is there a way to do this?

Bash Version is: GNU bash, Version 4.3.11(1)-release (x86_64-pc-linux-gnu)

Example:

$shopt -s autocd
$shopt autocd
autocd          on
$bash
$shopt autocd
autocd          off

Answer 1

You can export many shell options analogous to shell variables by using the corresponding shell variable BASHOPTS which stores the shell options:

export BASHOPTS

Here is some information of the Bash man page:

BASHOPTS: A colon-separated list of enabled shell options. Each word in the list is a valid argument for the -s option to the shopt builtin command (see SHELL BUILTIN COMMANDS below). The options appearing in BASHOPTS are those reported as on by shopt. If this variable is in the environment when bash starts up, each shell option in the list will be enabled before reading any startup files. This variable is read-only.

There is a closely related variable SHELLOPTS, but this only seems to work well if bash is invoked directly (e.g. via bash) rather than via sh because sh enables the POSIX mode of Bash. Here is more information on this issue.