rcmd man page on Solaris

Man page or keyword search:  
man Server   20652 pages
apropos Keyword Search (all sections)
Output format
Solaris logo
[printable version]

rcmd(3SOCKET)		   Sockets Library Functions		 rcmd(3SOCKET)

NAME
       rcmd,  rcmd_af, rresvport, rresvport_af, ruserok - routines for return‐
       ing a stream to a remote command

SYNOPSIS
       cc [ flag ... ] file... -lsocket -lnsl [ library... ]
       #include <netdb.h>
       #include <unistd.h>

       int rcmd(char **ahost, unsigned short inport, const char *luser,	 const
       char *ruser, const char *cmd, int *fd2p);

       int  rcmd_af(char  **ahost,  unsigned  short inport, const char *luser,
       const char *ruser, const char *cmd, int *fd2p, int af);

       int rresvport(int *port);

       int rresvport_af(int *port, int af);

       int ruserok(const char *rhost, int suser, const char *ruser, const char
       *luser);

DESCRIPTION
       The  rcmd() function is used by the superuser to execute a command on a
       remote machine with an authentication scheme  based  on	reserved  port
       numbers. An AF_INET socket is returned with rcmd(). The rcmd_af() func‐
       tion supports AF_INET, AF_INET6 or AF_UNSPEC for the address family. An
       application  can	 choose	 which	type  of socket is returned by passing
       AF_INET or AF_INET6 as the address family. The use of  AF_UNSPEC	 means
       that the caller will accept any address family. Choosing AF_UNSPEC pro‐
       vides a socket that best suits the connectivity to the remote host.

       The rresvport() function returns a  descriptor  to  a  socket  with  an
       address	in  the	 privileged port space. The rresvport_af() function is
       the equivalent to rresvport(), except that you can  choose  AF_INET  or
       AF_INET6 as the socket address family to be returned by rresvport_af().
       AF_UNSPEC does not apply to the rresvport() function.

       The ruserok() function is a routine used	 by  servers  to  authenticate
       clients that request as service with rcmd.

       All of these functions are present in the same file and are used by the
       in.rshd(1M) server among others.

       The rcmd() and rcmd_af() functions look up the host *ahost using getad‐
       drinfo(3SOCKET)	and  return −1 if the host does not exist.  Otherwise,
       *ahost is set to the standard name of the  host	and  a	connection  is
       established to a server residing at the Internet port inport.

       If  the	connection  succeeds,  a socket in the Internet domain of type
       SOCK_STREAM is returned to the caller.  The  socket  is	given  to  the
       remote  command as standard input (file descriptor 0) and standard out‐
       put (file descriptor 1). If fd2p is non-zero, an auxiliary channel to a
       control	process	 is set up and a descriptor for it is placed in *fd2p.
       The control process returns diagnostic output file (descriptor 2)  from
       the  command on the auxiliary channel. The control process also accepts
       bytes on this channel as signal numbers to be forwarded to the  process
       group of the command. If fd2p is 0, the standard error (file descriptor
       2) of the remote command is made the same as its	 standard  output.  No
       provision  is made for sending arbitrary signals to the remote process,
       other than possibly sending out-of-band data.

       The protocol is described in detail in in.rshd(1M).

       The rresvport() and rresvport_af()  functions  are  used	 to  obtain  a
       socket  bound  to  a privileged port number. The socket is suitable for
       use by rcmd() and rresvport_af() and several other routines. Privileged
       Internet	 ports are those in the range 1 to 1023. Only the superuser is
       allowed to bind a socket to a privileged port number.  The  application
       must  pass  in port, which must be in the range 512 to 1023. The system
       first tries to bind to that port number.	 If it fails, the system  then
       tries to bind to another unused privileged port, if one is available.

       The  ruserok()  function takes a remote host name returned by the geth‐
       ostbyaddr() function with two user names and a flag to indicate whether
       the  local  user's  name	 is  that  of  the  superuser.	See gethostby‐
       name(3NSL).   The   ruserok()   function	  then	 checks	  the	 files
       /etc/hosts.equiv	 and  possibly .rhosts in the local user's home direc‐
       tory to see if the request  for	service	 is  allowed.  A  0  value  is
       returned if the machine name is listed in the /etc/hosts.equiv file, or
       if the host and remote user name are found in the .rhosts file.	Other‐
       wise,  the  ruserok()  function returns −1. If the superuser flag is 1,
       the /etc/hosts.equiv is not checked.

       The error code EAGAIN is overloaded to mean "All network ports in use."

RETURN VALUES
       The rcmd() and rcmd_af() functions return  a  valid  socket  descriptor
       upon  success. The functions returns −1 upon error and print a diagnos‐
       tic message to standard error.

       The rresvport() and rresvport_af()  functions  return  a	 valid,	 bound
       socket descriptor upon success. The functions return −1 upon error with
       the global value errno set according to the reason for failure.

FILES
       /etc/hosts.equiv	       system trusted hosts and users

       ~/.rhosts	       user's trusted hosts and users

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       ┌─────────────────────────────┬─────────────────────────────┐
       │      ATTRIBUTE TYPE	     │	    ATTRIBUTE VALUE	   │
       ├─────────────────────────────┼─────────────────────────────┤
       │MT-Level		     │Unsafe			   │
       └─────────────────────────────┴─────────────────────────────┘

       This interface is Unsafe in multithreaded applications.	Unsafe	inter‐
       faces should be called only from the main thread.

SEE ALSO
       rlogin(1),   rsh(1),   in.rexecd(1M),   in.rshd(1M),  intro(2),	getad‐
       drinfo(3SOCKET), gethostbyname(3NSL), rexec(3SOCKET), attributes(5)

SunOS 5.10			  10 Feb 2004			 rcmd(3SOCKET)
[top]

List of man pages available for Solaris

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net