27.5. Dial-out Service
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## 27.5. 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.

### 27.5.1. 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`.

### 27.5.2. 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 -l`line` -s`speed``

`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.

### 27.5.3. 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=\@

### 27.5.4. 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`

### 27.5.5. 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.

### 27.5.6. 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:

### 27.5.7. 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.

### 27.5.8. 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`

### 27.5.9. 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.

### 27.5.10. 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.

### 27.5.11. 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.

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