REXEC(1)                                                 REXEC(1)

NAME
       rexec -- remote execution client for an exec server

SYNOPSIS
       rexec [ -abcdhns -l username -p password ] host command

DESCRIPTION
       Rexec  calls  the  rexec(3) routine to act as a client for
       the remote host's rexecd(8) server.

       It asks that ``command'' be  run  on  the  host  computer,
       using  username/password  authentication. See rexec(3) and
       rexecd(8) for details of the protocol.

OPTIONS
       Rexec accepts several options, but only three  are  likely
       to be very useful:

       -l username

              Set the log-in name on the remote host to username.

       -p password

              Provide the password for the remote  account.   The
              command  line  argument will be blanked after being
              parsed, to prevent it from being seen  with  ps(1).
              However,  it  is  still not very secure to type the
              password on the command line.   In  particular,  be
              sure that the shell's history file is protected.

       -n     Explicitly  prompt  for  name and password, even if
              provided in the environment,  in  the  $HOME/.netrc
              file,  or in the environmental variables REXEC_USER
              and REXEC_PASS.

       Other options  that  might  be  useful  with  non-standard
       remote exec daemons, or to debug connections:

       -a     Do  not  set  up  an auxiliary channel for standard
              error from command; the remote standard  error  and
              output are then both returned on the local standard
              output.  By default, rexec  asks  that  a  separate
              channel  be  set  up for diagnostic output from the
              remote command.

       -b     Use signal handling as in  BSD  rsh(1).   Only  the
              signals  SIGINT, SIGQUIT, and SIGTERM are echoed to
              the remote process.   They  do  not  remain  raised
              locally,  so  rexec waits for the remote command to
              shutdown its side of  the  socket.   Also,  CNTRL-Z
              will  only  suspend  execution  locally--the remote
              command may continue to run.

       -c     Do not close remote standard input when local stan-
              dard  input closes.  Normally the standard input to
              the remote command is closed when the  local  stan-
              dard input is closed.

       -d     Turn  on  debugging  information. In particular the
              command sent to the remote host will be echoed.

       -h     Print a usage message.

       -s     Do not echo signals received by the rexec onto  the
              remote  process.   Normally,  signals  which can be
              trapped are passed on to the remote process;  then,
              when  you  type  CNTRL-C, the remote process termi-
              nates as well.

USERNAME AND PASSWORD
       Rexec(1) searches for the username  and  password  in  the
       following order:

              1.  If  -n  is  given on the command line, the user
              will always be prompted for both, even if they  are
              also given on the command line.

              2. The command line will be parsed

              3.  If  the  environmental  variables REXEC_USER or
              REXEC_PASS are defined, they will define the  user-
              name or password.

              4.  The  $HOME/.netrc  file  will be searched.  See
              ftp(1) for a description of this file's format.

              5. Finally, the user will be prompted if either the
              username or password remains undefined.

SECURITY
       Users of this command should be aware that rexec(3) trans-
       mits their password to the remote  host  clear  text,  not
       encrypted.   If  the  network  is not secure to the remote
       host, the password can be comprimised.

SIGNALS
       Without the -b option, all signals which  can  be  handled
       are  echoed  to  the remote process.  Afterwards, however,
       they remain raised in the local process.  Typically,  this
       means that rexec(1) will exit after receiving a fatal sig-
       nal, even if the remote process has arranged to handle  or
       ignore it.

       Differing  operating systems use differing signal numbers;
       for example AIX and SunOS use 18 for SIGTSTP  (^Z),  while
       Linux  uses 20.  Therefore, it may have a different effect
       remotely than locally.  In particular, typing  CNTL-Z  may
       not suspend the execution of the remote process.

EXAMPLE
       rexec othermachine cat ">remote_file; date" <local_file

       will send local_file to the othermachine as remote_file.

BUGS
       Please send bug reports, system incompatibilities, and job
       offers to the author.

SEE ALSO
       rexec(3), rexecd(8), rsh(1)

AUTHOR
       Michael Sadd
       sadd@msc.cornell.edu
       http://www.msc.cornell.edu/~sadd/

       Thanks to  Orange  Gopher  (2/10/97)  and  Johannes  Plass
       (plass@dipmza.physik.uni-mainz.de,  Oct. 17 1996) for use-
       ful suggestions.

                        February 14, 1997                       1