2017-03-01 09:49:52 -0500, Chet Ramey: [...] > > Would you recommend people start adding: > > > > shopt -s compat44 2> /dev/null || true > > > > at the start of their script that they develop for bash-4.4 now > > so that it still works even when bash-6.0 makes a non-backward > > compatible change? > > I know this isn't a serious question, but I'll answer it anyway. > No. People should look at the effects of each compatibiity version > option and decide for themselves. > > > > > It seems there's a compatXX option for each of the versions > > since bash31. Will you keep doing it for every version? > > Most likely, but I will probably phase out the shopt options in > favor of BASH_COMPAT. [...]
Thanks, I wasn't aware of BASH_COMPAT. So instead of shopt -s compat44 2> /dev/null || true I could use: BASH_COMPAT=4.4 except that it gives a bash: BASH_COMPAT: 4.4: compatibility value out of range If run from an older version of bash (note that it does not set $? to non-zero nor triggers "set -e"). It seems I would want to specify the lowest version of bash I want to support in the script. Which makes sense. BTW, there seems to have been a regression in the handling of the -O option to the bash interpreter: $ ./bash -O compat31 -c 'echo "$BASH_VERSION"; [[ a =~ "." ]] && echo yes' 4.4.12(4)-maint $ ./bash -c 'echo "$BASH_VERSION"; shopt -s compat31; [[ a =~ "." ]] && echo yes' 4.4.12(4)-maint yes Was OK with 4.3: $ bash -O compat31 -c 'echo "$BASH_VERSION"; [[ a =~ "." ]] && echo yes' 4.3.46(1)-release yes (affects at least compat43 as well, not failglob for instance). -- Stephane
