Instructions for installing an atdialer.  In this example, atdialSP28 is used.

1. Move the dialer configuration (default) file into the defaults directory.
   On 3.2v4, the defaults directory is /etc/default.
   On 5.0, the defaults directory is /usr/lib/uucp/default.
2. Make it readable by uucp.
   chmod a+r atdialSP28
3. Link the atdialer program to the same name as the configuration file.
   cd /usr/lib/uucp
   ln atdialer atdialSP28

The atdialer is now ready to use.  Refer to it by name in the 5th field of the
/usr/lib/uucp/Devices file.

Some of the atdialers available here use a fixed DTE speed.  This means that
communications between the modem and the system always occur at the same speed,
regardless of what speed the modem communicates with the remote modem at.  The
modem converts between the two Baud rates, buffering data and invoking flow
control as neccessary.  The advantage of this is that it allows the use of
modem features that intrinsically cause the DCE (modem to modem) data rate to
vary ( particularly compression and error detection) as well as communications
at speeds that the serial driver does not understand (e.g. 14400).  Also, it
avoids the need for dialup users to cycle between different Baud rates by
sending break sequences.
Using a fixed DTE speed successfully has two requirements.  First, the modem
and serial port must both have functioning hardware (RTS/CTS) flow control.
The dialer takes care of configuring this, by telling the modem to do hardware
flow control and by setting the serial port to use it.  Additionally, you must
ensure that the cabling between the modem and serial port is sufficient for
hardware flow control.  A full 25-conductor cable will keep things simple.
Second, everything that uses the modem must talk to it at the fixed speed.
This means setting the speed for the modem line in the Devices file to the
fixed speed, and if the line is enabled for dialin, choosing a gettydefs tag
that will select a gettydefs entry with the appropriate speed (for example, "o"
for 38400 Baud).