net/rcmdsh.3

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  36 .Dd September 1, 1996
  37 .Dt RCMDSH 3
  38 .Os
  39 .Sh NAME
  40 .Nm rcmdsh
  41 .Nd return a stream to a remote command without superuser
  42 .Sh SYNOPSIS
  43 .In unistd.h
  44 .Ft int
  45 .Fo rcmdsh
  46 .Fa "char **ahost"
  47 .Fa "int inport"
  48 .Fa "const char *locuser"
  49 .Fa "const char *remuser"
  50 .Fa "const char *cmd"
  51 .Fa "const char *rshprog"
  52 .Fc
  53 .Sh DESCRIPTION
  54 The
  55 .Fn rcmdsh
  56 function
  57 is used by normal users to execute a command on
  58 a remote machine using an authentication scheme based
  59 on reserved port numbers using
  60 .Xr rshd 8
  61 or the value of
  62 .Fa rshprog
  63 (if
  64 .No non- Ns Dv NULL ) .
  65 .Pp
  66 The
  67 .Fn rcmdsh
  68 function
  69 looks up the host
  70 .Fa *ahost
  71 using
  72 .Xr gethostbyname 3 ,
  73 returning \-1 if the host does not exist.
  74 Otherwise
  75 .Fa *ahost
  76 is set to the standard name of the host
  77 and a connection is established to a server
  78 residing at the well-known Internet port
  79 .Dq Li shell/tcp
  80 (or whatever port is used by
  81 .Fa rshprog ) .
  82 The parameter
  83 .Fa inport
  84 is ignored; it is only included to provide an interface similar to
  85 .Xr rcmd 3 .
  86 .Pp
  87 If the connection succeeds,
  88 a socket in the
  89 .Ux
  90 domain of type
  91 .Dv SOCK_STREAM
  92 is returned to the caller, and given to the remote
  93 command as stdin, stdout, and stderr.
  94 .Sh RETURN VALUES
  95 The
  96 .Fn rcmdsh
  97 function
  98 returns a valid socket descriptor on success.
  99 Otherwise, \-1 is returned
 100 and a diagnostic message is printed on the standard error.
 101 .Sh SEE ALSO
 102 .Xr rsh 1 ,
 103 .Xr socketpair 2 ,
 104 .Xr rcmd 3 ,
 105 .Xr rshd 8
 106 .Sh BUGS
 107 If
 108 .Xr rsh 1
 109 encounters an error, a file descriptor is still returned instead of \-1.
 110 .Sh HISTORY
 111 The
 112 .Fn rcmdsh
 113 function first appeared in
 114 .Ox 2.0 ,
 115 and made its way into
 116 .Fx 5.0 .