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REXEC(3)               FreeBSD Library Functions Manual               REXEC(3)

NAME
     rexec - return stream to a remote command

LIBRARY
     Compatibility Library (libcompat, -lcompat)

SYNOPSIS
     int
     rexec(char **ahost, int inport, char *user, char *passwd, char *cmd,
         int *fd2p);

DESCRIPTION
     This interface is obsoleted by rcmd(3).

     The rexec() function looks up the host *ahost using gethostbyname(3),
     returning -1 if the host does not exist.  Otherwise *ahost is set to the
     standard name of the host.  If a username and password are both
     specified, then these are used to authenticate to the foreign host;
     otherwise the environment and then the user's .netrc file in his home
     directory are searched for appropriate information.  If all this fails,
     the user is prompted for the information.

     The port inport specifies which well-known DARPA Internet port to use for
     the connection; the call getservbyname("exec", "tcp") (see getservent(3))
     will return a pointer to a structure, which contains the necessary port.
     The protocol for connection is described in detail in rexecd(8).

     If the connection succeeds, a socket in the Internet domain of type
     SOCK_STREAM is returned to the caller, and given to the remote command as
     stdin and stdout.  If fd2p is non-zero, then an auxiliary channel to a
     control process will be setup, and a descriptor for it will be placed in
     *fd2p.  The control process will return diagnostic output from the
     command (unit 2) on this channel, and will also accept bytes on this
     channel as being UNIX signal numbers, to be forwarded to the process
     group of the command.  The diagnostic information returned does not
     include remote authorization failure, as the secondary connection is set
     up after authorization has been verified.  If fd2p is 0, then the stderr
     (unit 2 of the remote command) will be made the same as the stdout and no
     provision is made for sending arbitrary signals to the remote process,
     although you may be able to get its attention by using out-of-band data.

SEE ALSO
     rcmd(3), rexecd(8)

HISTORY
     The rexec() function appeared in 4.2BSD.

BUGS
     The rexec() function sends the unencrypted password across the network.

     The underlying service is considered a big security hole and therefore
     not enabled on many sites, see rexecd(8) for explanations.

FreeBSD 11.0-PRERELEASE          June 4, 1993          FreeBSD 11.0-PRERELEASE

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | SEE ALSO | HISTORY | BUGS

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