stty tostop
echo bar >&2 & # no output from echo, just from shell job control
fg # now the output is produced
    bar
text=$(echo foo; echo bar >&2) # command substitution in foreground command
    bar
text=$(echo /etc/passwd; echo bar >&2) ; ls -l "$text" &
    bar
fg
    -rw-r--r-- 1 root root 2745 18. Feb 00:36 /etc/passwd