UUCP Forwarding

When sending files through a series of machines, the intermediary machines must have the command uucp among their COMMANDS options. If you type the following command, the forwarding operation works only if machine willow permits machine oak to execute the uucp program.

% uucp sample.txt oak\!willow\!pine\!/usr/spool/uucppublic

The machine oak also must permit your machine to execute the uucp program. The machine pine, as the last machine designated, does not have to permit theuucp command because it is not doing any forwarding operations. Machines are not normally set up this way.

UUCP /etc/uucp/Poll File

The /etc/uucp/Poll file contains information for polling remote computers. Each entry in the Poll file contains the name of a remote computer to call, followed by a tab character or a space, and finally the hours the computer should be called. The format of entries in the Poll file are:

sys-name hour ...

For example, the entry

eagle 0 4 8 12 16 20 

provides polling of computer eagle every four hours.

The uudemon.poll script processes the Poll file but does not actually perform the poll. The script merely sets up a polling work file (always named C.file) in the spool directory. The uudemon.poll script starts the scheduler, and the scheduler examines all work files in the spool directory.

UUCP /etc/uucp/Config File

The /etc/uucp/Config file enables you to override certain parameters manually. Each entry in the Config file has this format:

parameter=value

See the Config file that is provided with your system for a complete list of configurable parameter names.

The following Config entry sets the default protocol ordering to Gge and changes the G protocol defaults to 7 windows and 512-byte packets.

Protocol=G(7,512)ge

UUCP/etc/uucp/Grades File

The /etc/uucp/Grades file contains the definitions for the job grades that can be used to queue jobs to a remote computer. This file also contains the permissions for each job grade. Each entry in this file represents a definition of an administrator-defined job grade that lets users queue jobs.

Each entry in the Grades file has the following format:

User-job-grade System-job-grade Job-size Permit-type ID-list

Each entry contains fields that are separated by blank space. The last field in the entry is composed of subfields that are also separated by spaces. If an entry occupies more than one physical line, you can use a backslash to continue the entry onto the following line. Comment lines begin with a pound sign (#) and occupy the entire line. Blank lines are always ignored.

UUCP User-job-grade Field

This field contains an administrative-defined user job grade name of up to 64 characters.

UUCP System-job-grade Field

This field contains a single-character job grade to which User-job-grade is mapped. The valid list of characters is A-Z, a-z, with A having the highest priority and z the lowest.

Relationship Between User and System Job Grades

The user job grade can be bound to more than one system job grade. Note that the Grades file is searched sequentially for occurrences of a user job grade. Therefore, any multiple occurrences of a system job grade should be listed in compliance with the restriction on the maximum job size.

While no maximum number exists for the user job grades, the maximum number of system job grades that are allowed is 52. The reason is that more than one User-job-grade can be mapped to a System-job-grade, but each User-job-grade must be on a separate line in the file. Here is an example:

mail N Any User Any netnews N Any User Any 

If this configuration is in a Grades file, these two User-job-grade fields share the same System-job-grade. Because the permissions for a Job-grade are associated with a User-job-grade and not a System-job-grade, two User-job-grades can share the same System-job-grades and have two different sets of permissions.

Default Grade

You can define the binding of a default User-job-grade to a system job grade. You must use the keyword default as user job grade in the User-job-grade field of the Grades file and the system job grade that it is bound to. The Restrictions and ID fields should be defined as Any so that any user and any size job can be queued to this grade. Here is an example:

default a Any User Any 

If you do not define the default user job grade, the built-in default grade Z is used. Because the restriction field default is Any, multiple occurrences of the default grade are not checked.

UUCP Job-size Field

This field specifies the maximum job size that can be entered in the queue. Job-size is measured in bytes and can be a list of the options that are listed in the following table.

Table 40-8 Job-size Field

Here are some examples:

• 5000 represents 5000 bytes

• 10K represents 10 Kbytes

• 2M represents 2 Mbytes

UUCP Permit-type Field

This field contains a keyword that denotes how to interpret the ID list. The following table lists the keywords and their meanings.

Table 40-9 Permit-type Field

UUCP ID-list Field

This field contains a list of login names or group names that are to be permitted or denied queuing to this job grade. The list of names are separated by a blank space and terminated by a newline character. The keyword Any is used to denote that anyone is permitted to queue to this job grade.

Other UUCP Configuration Files

This section describes three less-frequently modified files that impact the use of UUCP facilities.

UUCP /etc/uucp/Devconfig File

The /etc/uucp/Devconfig file enables you to configure devices by service--uucp or cu. Devconfig entries define the STREAMS modules that are used for a particular device. They have the following format:

service=x device=y push=z[:z...]

x can be cu, uucico, or both services separated by a colon. y is the name of a network and must match an entry in the Devices file. z is replaced by the names of STREAMS modules in the order that they are to be pushed onto the Stream. Different modules and devices can be defined for cu and uucp services.

The following entries are for a STARLAN network and would most commonly be used in the file:

service=cu       device=STARLAN     push=ntty:tirdwr 
service=uucico   device=STARLAN     push=ntty:tirdwr 

This example pushes ntty, then tirdwr.

UUCP /etc/uucp/Limits File

The /etc/uucp/Limits file controls the maximum number of simultaneous uucicos, uuxqts, and uuscheds that are running in the uucp networking. In most situations, the default values are acceptable and no changes are needed. If you want to change them, however, use any text editor.

The format of the Limits file is as follows:

service=x max=y:

x can be uucico, uuxqt or uusched, and y is the limit that is permitted for that service. The fields can be in any order and in lowercase.

The following entries should most commonly be used in the Limits file:

service=uucico max=5 
service=uuxqt max=5 
service=uusched max=2 

The example allows five uucicos, five uuxqts, and two uuscheds running on your machine.