User`s guide

The AXEL Proprietary Network Servers
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64 TCP/IP AXEL Platine Terminal
8.1.3 - Device: Pseudo-Terminal or Named Pipe
The device used by the printd server can be either a pseudo-terminal or a
named pipe. Consider the following when choosing:
Named Pipe:
The use of a named pipe is very versatile. Because named pipes are not
attached to UNIX kernel drivers, it is possible to create as many as
necessary. However, these devices only provide uni-directional
communication.
Pseudo Terminal:
This is a pair of devices (master and slave parts) set and used, as a
standard feature, by UNIX systems. As the number of devices is limited, it
is possible that other software may compete with the printd server for a
given pseudo-terminal. However, under most UNIX versions, it is easy to
increase the number of pseudo-terminals.
Notes:
- The printd server controls both named pipes and pseudo-terminals.
- The ttyd server controls only pseudo-terminals.
- No UNIX device is used by the rprint server.
8.1.4 - TCP Port Number
As an AXEL server can control three ports of the same Platine terminal, each
port on a Platine must be identified.
This identification is done by assigning a TCP port number to each port. The
port can then be identified by the pair: Platine terminal IP address, TCP port
number.
Note: the three ports of a Platine terminal must each have a different port
number.
IMPORTANT: a TCP port number must be entered through:
- Terminal Set-Up on the Platine terminal,
- and the AXEL server configurator (/etc/axconf).