Axel AX3000 65 User's Manual - Manual (Page 100)

Installing under UNIX/LINUX
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AX3000 - User's Manual
5.4 - THE AXEL TTY SERVER
5.4.1 - 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
terminal is accessed by Unix as a local printer via /dev/ttyp4, which may be
preferable over using LPD in certain circumstances. Similarly the Axel terminal
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).