Axel AX3000 80, User Manual

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Installing under UNIX/LINUX
AX3000 Models 80 and 85 - User's Manual
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Note : the default printer port is also used to perform local printing of the screen using the <Prt Scr>
key.
8.4 - THE AXEL TTY SERVER
8.4.1 - Overview
The TTY server emulates a multi i/o board connection over a TCP/IP connection. For example
using this service a remote printer attached to an Axel thin client is accessed by Unix as a local
printer via /dev/ttyp4, which may be preferable over using LPD in certain circumstances. Similarly
the Axel thin client can be accessed via a predetermined and fixed /dev/ttyp, which in certain cases
may be preferable over using telnet.
The AXEL tty server is a UNIX daemon (axttyd). The axttyd daemon must be used with the AX3000
tty or rtty network service.
The AXEL tty server creates a ‘pipe’ between pseudo devices on the UNIX host (/dev/ttypx) and
AX3000 resources (sessions and/or auxiliary ports). This ‘pipe’ lets Unix treat the Axel sessions
and auxiliary ports as local resources.
Note about pseudo-terminals : a pseudo-terminal is composed of two parts: a master file and a
slave file. UNIX supports two possible styles for naming pttys:
- One master and X slaves (AT&T style): the master filename is /dev/ptmx and the slave
filenames are /dev/pts/xxx (where xxx is a number).
- X masters and X slaves (Berkeley style): the master filename is /dev/ptypxxx and the slave
filenames are /dev/ttypxxx (where xxx is the same number for master and slave).
The following drawing shows the Unix/Linux mechanisms:
Socket
TCP Stack
AXEL
tty server
AX3000 TCP/IP Terminal
UNIX
ttypz ptypz
(slave) (master)
ttypy ptypy
(slave) (master)
ttypx ptypx
(slave) (master)
Software
Software
Software