1trap 'echo USR1 $BASHPID' USR1 2trap 'echo foo $BASH_SUBSHELL' 0 3 4trap | cat 5echo between 6( trap ) 7echo between 2 8{ trap; } | cat 9 10( echo in subshell: $BASH_SUBSHELL ) 11( echo in subshell pipeline: $BASH_SUBSHELL ) | cat 12 13{ echo group pipeline: $BASH_SUBSHELL; 14 trap 'echo EXIT-group.$BASH_SUBSHELL' EXIT; } | cat 15