26.5. Dial-out Service

The following are tips for getting the host to connect over the modem to another computer. This is appropriate for establishing a terminal session with a remote host.

This kind of connection can be helpful to get a file on the Internet if there are problems using PPP. If PPP is not working, use the terminal session to FTP the needed file. Then use zmodem to transfer it to the machine.

26.5.1. Using a Stock Hayes Modem

A generic Hayes dialer is built into tip. Use at=hayes in /etc/remote.

The Hayes driver is not smart enough to recognize some of the advanced features of newer modems messages like BUSY, NO DIALTONE, or CONNECT 115200. Turn those messages off when using tip with ATX0&W.

The dial timeout for tip is 60 seconds. The modem should use something less, or else tip will think there is a communication problem. Try ATS7=45&W.

26.5.2. Using AT Commands

Create a direct entry in /etc/remote. For example, if the modem is hooked up to the first serial port, /dev/cuau0, use the following line:

cuau0:dv=/dev/cuau0:br#19200:pa=none

Use the highest bps rate the modem supports in the br capability. Then, type tip cuau0 to connect to the modem.

Or, use cu as root with the following command:

# cu -lline -sspeed

line is the serial port, such as /dev/cuau0, and speed is the speed, such as 57600. When finished entering the AT commands, type ~. to exit.

26.5.3. The @ Sign Does Not Work

The @ sign in the phone number capability tells tip to look in /etc/phones for a phone number. But, the @ sign is also a special character in capability files like /etc/remote, so it needs to be escaped with a backslash:

pn=\@

26.5.4. Dialing from the Command Line

Put a generic entry in /etc/remote. For example:

tip115200|Dial any phone number at 115200 bps:\
        :dv=/dev/cuau0:br#115200:at=hayes:pa=none:du:
tip57600|Dial any phone number at 57600 bps:\
        :dv=/dev/cuau0:br#57600:at=hayes:pa=none:du:

This should now work:

# tip -115200 5551234

Users who prefer cu over tip, can use a generic cu entry:

cu115200|Use cu to dial any number at 115200bps:\
        :dv=/dev/cuau1:br#57600:at=hayes:pa=none:du:

and type:

# cu 5551234 -s 115200

26.5.5. Setting the bps Rate

Put in an entry for tip1200 or cu1200, but go ahead and use whatever bps rate is appropriate with the br capability. tip thinks a good default is 1200 bps which is why it looks for a tip1200 entry. 1200 bps does not have to be used, though.

26.5.6. Accessing a Number of Hosts Through a Terminal Server

Rather than waiting until connected and typing CONNECT host each time, use tip's cm capability. For example, these entries in /etc/remote will let you type tip pain or tip muffin to connect to the hosts pain or muffin, and tip deep13 to connect to the terminal server.

pain|pain.deep13.com|Forrester's machine:\
        :cm=CONNECT pain\n:tc=deep13:
muffin|muffin.deep13.com|Frank's machine:\
        :cm=CONNECT muffin\n:tc=deep13:
deep13:Gizmonics Institute terminal server:\
        :dv=/dev/cuau2:br#38400:at=hayes:du:pa=none:pn=5551234:

26.5.7. Using More Than One Line with tip

This is often a problem where a university has several modem lines and several thousand students trying to use them.

Make an entry in /etc/remote and use @ for the pn capability:

big-university:\
        :pn=\@:tc=dialout
dialout:\
        :dv=/dev/cuau3:br#9600:at=courier:du:pa=none:

Then, list the phone numbers in /etc/phones:

big-university 5551111
big-university 5551112
big-university 5551113
big-university 5551114

tip will try each number in the listed order, then give up. To keep retrying, run tip in a while loop.

26.5.8. Using the Force Character

Ctrl+P is the default force character, used to tell tip that the next character is literal data. The force character can be set to any other character with the ~s escape, which means set a variable.

Type ~sforce=single-char followed by a newline. single-char is any single character. If single-char is left out, then the force character is the null character, which is accessed by typing Ctrl+2 or Ctrl+Space. A pretty good value for single-char is Shift+Ctrl+6, which is only used on some terminal servers.

To change the force character, specify the following in ~/.tiprc:

force=single-char

26.5.9. Upper Case Characters

This happens when Ctrl+A is pressed, which is tip's raise character, specially designed for people with broken caps-lock keys. Use ~s to set raisechar to something reasonable. It can be set to be the same as the force character, if neither feature is used.

Here is a sample ~/.tiprc for Emacs users who need to type Ctrl+2 and Ctrl+A:

force=^^
raisechar=^^

The ^^ is Shift+Ctrl+6.

26.5.10. File Transfers with tip

When talking to another UNIX®-like operating system, files can be sent and received using ~p (put) and ~t (take). These commands run cat and echo on the remote system to accept and send files. The syntax is:

~p local-file [remote-file]

~t remote-file [local-file]

There is no error checking, so another protocol, like zmodem, should probably be used.

26.5.11. Using zmodem with tip?

To receive files, start the sending program on the remote end. Then, type ~C rz to begin receiving them locally.

To send files, start the receiving program on the remote end. Then, type ~C sz files to send them to the remote system.

All FreeBSD documents are available for download at http://ftp.FreeBSD.org/pub/FreeBSD/doc/

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