sys entry in the following way:

system       pablo

phone        123-456

.. entries as above ...

alternate

phone        123-455

system pablo phone 123-456… entries as above… alternate phone 123-455

When calling pablo, uucico will first dial 123-456, and if this fails, it will try the alternate. The alternate entry retains all settings from the main system entry and overrides the telephone number only.

Restricting call times

Taylor UUCP provides a number of ways you may restrict the times when calls can be placed to a remote system. You might do this either because of limitations the remote host places on its services during business hours, or simply to avoid times with high call rates. Note that it is always possible to override call-time restrictions by giving uucico the -S or -f option.

By default, Taylor UUCP disallows connections at any time, so you have to use some sort of time specification in the sys file. If you don't care about call time restrictions, you can specify the time option with a value of Any in your sys file.

The simplest way to restrict call time is to include a time entry, followed by a string made up of a day and a time subfield. Day may be any combination of Mo, Tu, We, Th, Fr, Sa, and Su. You can also specify Any, Never, or Wk for weekdays. The time consists of two 24-hour clock values, separated by a dash. They specify the range during which calls may be placed. The combination of these tokens is written without white space in between. Any number of day and time specifications may be grouped together with commas, as this line shows:

time MoWe0300-0730,Fr1805-2200

This example allows calls on Mondays and Wednesdays from 3:00 a.m. to 7:30 a.m., and on Fridays between 6:05 p.m. and 10:00 p.m. When a time field spans midnight, say Mo1830-0600, it actually means Monday, between midnight and 6:00 a.m. and between 6:30 p.m. and midnight.

The special time strings Any and Never mean what they say: calls may be placed at any or no time, respectively.

Taylor UUCP also has a number of special tokens you may use in time strings, such as NonPeak and Night. These special tokens are shorthand for Any2300-0800,SaSu0800-1700 and Any1800-0700,SaSu, respectively.

The time command takes an optional second argument that describes a retry time in minutes. When an attempt to establish a connection fails, uucico will not allow another attempt to dial up the remote host within a certain interval. For instance, when you specify a retry time of 5 minutes, uucico will refuse to call the remote system within 5 minutes after the last failure. By default, uucico uses an exponential backoff scheme, where the retry interval increases with each repeated failure.

The timegrade command allows you to attach a maximum spool grade to a schedule. For instance, assume you have the following timegrade commands in a system entry:

timegrade           N Wk1900-0700,SaSu

timegrade           C Any

This allows jobs with a spool grade of C or higher (usually mail is queued with grade B or C) to be transferred whenever a call is established, while news (usually queued with grade N) are transferred only during the night and at weekends.

Just like time, the timegrade command takes a retry interval in minutes as an optional third argument.

However, a caveat about spool grades is in order here. First, the timegrade option applies only to what your systems sends; the remote system may still transfer anything it likes. You can use the call-timegrade option to explicitly request it to send only jobs above some given spool grade; but there's no guarantee it will obey this request.[97]

Similarly, the timegrade field is not checked when a remote system calls in, so any jobs queued for the calling system will be sent. However, the remote system can explicitly request your uucico to restrict itself to a certain spool grade.

Identifying Available Devices Through the port File

The port file tells uucico about the available ports. These are usually modem ports, but other types, such as direct serial lines and TCP sockets, are supported as well.

Like the sys file, port consists of separate entries starting with the keyword port followed by the port name. This name may be used in the sys file's port statement. The name need not be unique; if there are several ports with the same name, uucico will try each in turn until it finds one that is not currently being used.

The port command should be followed immediately by the type statement, which indicates what type of port is described. Valid types are modem, direct for direct connections, and tcp for TCP sockets. If the port command is missing, the port type defaults to modem.

In this section, we cover only modem ports; TCP ports and direct lines are discussed in a later section.

For modem and direct ports, you have to specify the device for calling out using the device directive. Usually, this is the name of a device special file in the /dev directory, like /dev/ttyS1.

In the case of a modem device, the port entry also determines what type of modem is connected to the port. Different types of modems have to be configured differently. Even modems that claim to be Hayes-compatible aren't always really compatible with one another. Therefore, you have to tell uucico how to initialize the modem and make it dial the desired number. Taylor UUCP keeps the descriptions of all dialers in a file named dial. To use any of these, you have to specify the dialer's name using the dialer command.

Sometimes, you will want to use a modem in different ways, depending on which system you call. For instance, some older modems don't understand when a high-speed modem attempts to connect at 56 kbps; they simply drop the line instead of negotiating a connect at 9,600 bps, for instance. When you know site drop uses such a dumb modem, you have to set up your modem differently when calling them. For this, you need an additional port entry in the port file that specifies a different dialer. Now you can give the new port a different name, such as serial1-slow, and use the port directive in the drop system entry in sys.

A better to distinguish the ports is by the speeds they support. For instance, the two port entries for the above situation may look like this:

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