upstream commit

Clarify pseudo-terminal request behaviour and use
 "pseudo-terminal" consistently.  bz#1716, ok jmc@ "I like it" deraadt@.
diff --git a/ssh.1 b/ssh.1
index da64b71..dd01b97 100644
--- a/ssh.1
+++ b/ssh.1
@@ -33,8 +33,8 @@
 .\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 .\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 .\"
-.\" $OpenBSD: ssh.1,v 1.356 2015/03/03 06:48:58 djm Exp $
-.Dd $Mdocdate: March 3 2015 $
+.\" $OpenBSD: ssh.1,v 1.357 2015/05/06 05:45:17 dtucker Exp $
+.Dd $Mdocdate: May 6 2015 $
 .Dt SSH 1
 .Os
 .Sh NAME
@@ -584,9 +584,9 @@
 .Xr sftp 1 ) .
 The subsystem is specified as the remote command.
 .It Fl T
-Disable pseudo-tty allocation.
+Disable pseudo-terminal allocation.
 .It Fl t
-Force pseudo-tty allocation.
+Force pseudo-terminal allocation.
 This can be used to execute arbitrary
 screen-based programs on a remote machine, which can be very useful,
 e.g. when implementing menu services.
@@ -876,15 +876,26 @@
 host key is not known or has changed.
 .Pp
 When the user's identity has been accepted by the server, the server
-either executes the given command, or logs into the machine and gives
-the user a normal shell on the remote machine.
+either executes the given command in a non-interactive session or,
+if no command has been specified, logs into the machine and gives
+the user a normal shell as an interactive session.
 All communication with
 the remote command or shell will be automatically encrypted.
 .Pp
-If a pseudo-terminal has been allocated (normal login session), the
+If an interactive session is requested
+.Nm
+by default will only request a pseudo-terminal (pty) for interactive
+sessions when the client has one.
+The flags
+.Fl T
+and
+.Fl t
+can be used to override this behaviour.
+.Pp
+If a pseudo-terminal has been allocated the
 user may use the escape characters noted below.
 .Pp
-If no pseudo-tty has been allocated,
+If no pseudo-terminal has been allocated,
 the session is transparent and can be used to reliably transfer binary data.
 On most systems, setting the escape character to
 .Dq none