rcmd(1) - NetBSD Manual Pages

RCMD(1)                 NetBSD General Commands Manual                 RCMD(1)


NAME

     rcmd -- backend driver for rcmd(3)


SYNOPSIS

     rcmd [-46dn] [-l username] [-p port] [-u localusername] host command


DESCRIPTION

     rcmd executes command on host.

     rcmd copies its standard input to the remote command, the standard output
     of the remote command to its standard output, and the standard error of
     the remote command to its standard error.  Interrupt, quit and terminate
     signals are propagated to the remote command; rcmd normally terminates
     when the remote command does.  The options are as follows:

     -4    Use IPv4 addresses only.

     -6    Use IPv6 addresses only.

     -d    The -d option turns on socket debugging (using setsockopt(2)) on
           the TCP sockets used for communication with the remote host.

     -l    By default, the remote username is the same as the local username.
           The -l option allows the remote name to be specified.  Another pos-
           sible way to specify the remote username is the notation user@host.

     -n    The -n option redirects input from the special device /dev/null
           (see the BUGS section of this manual page).

     -p port
           Uses the given port instead of the one assigned to the service
           ``shell''.  May be given either as symbolic name or as number.

     -u    The -u option allows the local username to be specified.  Only the
           superuser is allowed to use this option.

     Shell metacharacters which are not quoted are interpreted on local
     machine, while quoted metacharacters are interpreted on the remote
     machine.  For example, the command

           rcmd otherhost cat remotefile >> localfile

     appends the remote file remotefile to the local file localfile, while

           rcmd otherhost cat remotefile ">>" other_remotefile

     appends remotefile to other_remotefile.


FILES

     /etc/hosts


SEE ALSO

     rsh(1), rcmd(3), environ(7)


HISTORY

     The rcmd command appeared in NetBSD 1.3 and is primarily derived from
     rsh(1).  Its purpose was to create a backend driver for rcmd(3) that
     would allow the users of rcmd(3) to no longer require super-user privi-
     leges.


BUGS

     If you are using csh(1) and put a rcmd in the background without redi-
     recting its input away from the terminal, it will block even if no reads
     are posted by the remote command.  If no input is desired you should re-
     direct the input of rcmd to /dev/null using the -n option.

     You cannot use rcmd to run an interactive command (like rogue(6) or
     vi(1)).  Use rlogin(1) instead.

     The stop signal, SIGSTOP, will stop the local rcmd process only.  This is
     arguably wrong, but currently hard to fix for reasons too complicated to
     explain here.

NetBSD 9.3                       May 31, 2011                       NetBSD 9.3