config root man

    The command ARG is to be read and executed when the shell receives
    signal(s) SIGNAL_SPEC.  If ARG is absent (and a single SIGNAL_SPEC
    is supplied) or `-', each specified signal is reset to its original
    value.  If ARG is the null string each SIGNAL_SPEC is ignored by the
    shell and by the commands it invokes.  If a SIGNAL_SPEC is EXIT (0)
    the command ARG is executed on exit from the shell.  If a SIGNAL_SPEC
    is DEBUG, ARG is executed after every simple command.  If the`-p' option
    is supplied then the trap commands associated with each SIGNAL_SPEC are
    displayed.  If no arguments are supplied or if only `-p' is given, trap
    prints the list of commands associated with each signal.  Each SIGNAL_SPEC
    is either a signal name in <signal.h> or a signal number.  Signal names
    are case insensitive and the SIG prefix is optional.  `trap -l' prints
    a list of signal names and their corresponding numbers.  Note that a
    signal can be sent to the shell with "kill -signal $$".