The shopt options are set with
arg (see shopt options).
Versions of bash prior to 2.0 had environment
variables to perform some of these settings. Setting them equated to
shopt -s. The variables (and
corresponding shopt options) were:
allow_null_glob_expansion (nullglob), cdable_vars
(cdable_vars), command_oriented_history (cmdhist), glob_dot_filenames
(dotglob), no_exit_ on_failed_exec (execfail). These variables
no longer exist.
gnu_errfmt are not available in versions of
bash prior to 3.0.
Table A-7. shopt options
Meaning if set
An argument to cd that is not a directory is assumed to be the name of a variable whose value is the directory to change to.
Minor errors in the spelling of a directory supplied to the cd command will be corrected if there is a suitable match. This correction includes missing letters, incorrect letters, and letter transposition. It works for interactive shells only.
Commands found in the hash table are checked for
existence before being executed and nonexistence forces a
Checks the window size after each command and, if
it has changed, updates the variables
Attempt to save all lines of a multiline command in a single history entry.
Filenames beginning with a . are included in pathname expansion.
A noninteractive shell will not exit if it cannot execute ...