UUCP Dialer-Token-Pairs Field
The Dialer-Token-Pairs (DTP) field contains the name of a dialer and the token to pass it. The DTP field has this syntax:
dialer token [dialer token]
The dialer portion can be the name of a modem, a port monitor, or it can be direct or uudirect for a direct-link device. You can have any number of dialer-token pairs. If the dialer portion is not present, it is taken from a related entry in the Systems file. The token portion can be supplied immediately after the dialer portion.
The last dialer-token pair might not be present, depending on the associated dialer. In most situations, the last pair contains only a dialer portion. The token portion is retrieved from the Phone field of the associated Systems file entry.
A valid entry in the dialer portion can be defined in the Dialers file or can be one of several special dialer types. These special dialer types are compiled into the software and are therefore available without having entries in the Dialers file. The following table shows the special dialer types.
Table 40-3 Dialer-Token Pairs
TCP/IP network | |
Transport Level Interface Network (without STREAMS) | |
Transport Level Interface Network (with STREAMS) |
See "UUCP Protocol Definitions in the Devices File" for more information.
Structure of the Dialer-Token-Pairs Field
The DTP field can be structured four different ways, depending on the device that is associated with the entry:
Directly connected modem
If a modem is connected directly to a port on your computer, the DTP field of the associated Devices file entry has only one pair. This pair would normally be the name of the modem. This name is used to match the particular Devices file entry with an entry in the Dialers file. Therefore, the Dialer field must match the first field of a Dialers file entry.
Example 40-7 Dialers Field for Direct Connect Modem
Dialers hayes =,-, "" \\dA\pTE1V1X1Q0S2=255S12=255\r\c
\EATDT\T\r\c CONNECT
|
Notice that only the dialer portion (hayes) is present in the DTP field of the Devices file entry. This means that the token to be passed on to the dialer (in this instance, the phone number) is taken from the Phone field of a Systems file entry. (\T is implied, as described in Example 40-9.)
Direct link - For a direct link to a particular computer, the DTP field of the associated entry would contain the keyword direct. This is true for both types of direct-link entries, Direct and Sys-Name (refer to "UUCP Type Field").
Computers on the same port selector - If a computer with which you intend to communicate is on the same port selector switch as your computer, your computer must first access the switch. The switch then makes the connection to the other computer. This type of entry has only one pair. The dialer portion is used to match a Dialers file entry.
Example 40-8 UUCP Dialers Field for Computers on Same Port Selector
Dialers develcon ,"" "" \pr\ps\c est:\007 \E\D\e \007 |
As shown, the token portion is left blank. This designation indicates that it is retrieved from the Systems file. The Systems file entry for this computer contains the token in the Phone field, which is normally reserved for the phone number of the computer. Refer to "UUCP /etc/uucp/Systems File" for details. This type of DTP contains an escape character (\D), which ensures that the contents of the Phone field are not interpreted as a valid entry in the Dialcodes file.
Modems that are connected to port selector - If a high-speed modem is connected to a port selector, your computer must first access the port selector switch. The switch makes the connection to the modem. This type of entry requires two dialer-token-pairs. The dialer portion of each pair (fifth and seventh fields of entry) is used to match entries in the Dialers file, as shown below.
Example 40-9 UUCP Dialers Field for Modems Connected to Port Selector
Dialers develcon "" "" \pr\ps\c est:\007 \E\D\e \007 Dialers ventel =&-% t"" \r\p\r\c $ <K\T%\r>\c ONLINE! |
In the first pair, develcon is the dialer and vent is the token that is passed to the Develcon switch to tell it which device (such as Ventel modem) to connect to your computer. This token is unique for each port selector, as each switch can be set up differently. After the Ventel modem has been connected, the second pair is accessed. Ventel is the dialer and the token is retrieved from the Systems file.
Two escape characters can appear in a DTP field:
\T - Indicates that the Phone (token) field should be translated by using the /etc/uucp/Dialcodes file. This escape character is normally placed in the /etc/uucp/Dialers file for each caller script that is associated with a modem (Hayes, US Robotics, and so on). Therefore, the translation does not occur until the caller script is accessed.
\D - Indicates that the Phone (token) field should not be translated by using the /etc/uucp/Dialcodes file. If no escape character is specified at the end of a Devices entry, the \D is assumed (default). A \D is also used in the /etc/uucp/Dialers file with entries that are associated with network switches (develcon and micom).
UUCP Protocol Definitions in the Devices File
You can define the protocol to use with each device in /etc/uucp/Devices. This specification is usually unnecessary because you can use the default or define the protocol with the particular system you are calling. Refer to "UUCP /etc/uucp/Systems File" for details. If you do specify the protocol, you must use the following form:
Type,Protocol [parameters]
For example, you can use TCP,te to specify the TCP/IP protocol.
The following table shows the available protocols for the Devices file.
Table 40-4 Protocols Used in /etc/uucp/Devices
Protocol | Description |
|---|---|
This protocol is commonly used for transmissions over TCP/IP and other reliable connections. t assumes error-free transmissions. | |
This protocol is UUCP's native protocol. It is slow, reliable, and good for transmission over noisy telephone lines. | |
This protocol assumes transmission over error-free channels that are message oriented (as opposed to byte-stream oriented, such as TCP/IP). | |
This protocol is used for transmission over X.25 connections. f relies on flow control of the data stream, and is meant for working over links that can (almost) be guaranteed to be error-free, specifically X.25/PAD links. A checksum is enacted over a whole file only. If a transport fails, the receiver can request retransmission(s). |
Here is an example that shows a protocol designation for a device entry:
TCP,te - - Any TCP - |
This example indicates that, for device TCP, you should try to use the t protocol. If the other end refuses, use the e protocol.
Neither e nor t is appropriate for use over modems. Even if the modem assures error-free transmission, data can still be dropped between the modem and the CPU.
UUCP /etc/uucp/Dialers File
The /etc/uucp/Dialers file contains dialing instructions for many commonly used modems. You probably do not need to change or add entries to this file unless you plan to use a nonstandard modem or plan to customize your UUCP environment. Nevertheless, you should understand what is in the file and how it relates to the Systems and Devices file.
The text specifies the initial conversation that must occur on a line before it can be made available for transferring data. This conversation, often referred to as a chat-script, is usually a sequence of ASCII strings that is transmitted and expected, and it is often used to dial a phone number.
As shown in the examples in "UUCP /etc/uucp/Devices File", the fifth field in a Devices file entry is an index into the Dialers file or a special dialer type (TCP, TLI, or TLIS). The uucico daemon attempts to match the fifth field in the Devices file with the first field of each Dialers file entry. In addition, each odd-numbered Devices field, starting with the seventh position, is used as an index into the Dialers file. If the match succeeds, the Dialers entry is interpreted to perform the dialer conversation.
Each entry in the Dialers file has the following format:
|
|
|
The following example shows the entry for a US Robotics V.32bis modem.
Example 40-10 /etc/uucp/Dialers File Entry
Dialer Substitution Expect-Send
usrv32bis-e =,-, "" dA\pT&FE1V1X1Q0S2=255S12=255&A1&H1&M5&B2&W\r\c OK\r
\EATDT\T\r\c CONNECT\s14400/ARQ STTY=crtscts
|
The Dialer field matches the fifth and additional odd-numbered fields in the Devices file. The Substitutions field is a translate string: the first of each pair of characters is mapped to the second character in the pair. This mapping is usually used to translate = and - into whatever the dialer requires for "wait for dial tone" and "pause."
The remaining expect-send fields are character strings.
The following example shows some sample entries in the Dialers file, as distributed when you install UUCP as part of the Solaris installation program.
Example 40-11 Excerpts From /etc/uucp/Dialers