oneline_if_else.sh

# docs: https://stackoverflow.com/questions/28353244/error-in-linux-console-couldnt-get-a-file-descriptor-referring-to-the-console

if [[ `tty` =~ ^/dev/tty[0-9]+ ]] ; then setfont ... ; fi
if [[ `tty` =~ ^/dev/tty[0-9]+ ]] ; then  echo "setfont ..." ; else echo "not setfont" ; fi