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unix v7是最后一个广泛发布的研究型UNIX版本

(e.g. cua0),
(Hardwired lines have a number ``0'' in this field.),
.IP speed
is the line speed.
.RE
.LP
The line
.IP "" 12
cul0\ \ cua0\ \ 300
.LP
would be set up for a system which
had device cul0 wired to a call-unit
cua0 for use at 300 baud.
.SH
L-dialcodes
.LP
This file contains entries with location abbreviations used
in the
.I L.sys
file (e.g. py, mh, boston).
The entry format is
.IP "" 12
abb\ \ dial-seq
.LP
where;
.RS
.IP abb 12
is the abbreviation,
.IP dial-seq
is the dial sequence to call that location.
.RE
.LP
The line
.IP "" 12
py\ \ 165\-
.LP
would be set up so that entry py7777 would
send 165\-7777 to the dial-unit.
.SH
LOGIN/SYSTEM NAMES
.LP
It is assumed that the
.I "login name"
used by a remote computer to call into a local computer
is not the same as the login name of a normal user
of that local machine.
However, several remote computers may employ the same
login name.
.LP
Each computer is given a unique
.I "system name"
which is transmitted at the start of each call.
This name identifies the calling machine to the called machine.
.SH
USERFILE
.LP
This file contains user accessibility information.
It specifies four types of constraint;
.RS
.IP [1]
which files can be accessed by a normal user of the local machine,
.IP [2]
which files can be accessed from a remote computer,
.IP [3]
which login name is used by a particular remote computer,
.IP [4]
whether a remote computer should be called back in order to confirm
its identity.
.RE
.LP
Each line in the file has the following format
.IP "" 6
login,sys\ \ 
.B [
c
.B ]
\ \ path-name\ \ 
.B [
path-name
.B ]
\ ...
.LP
where;
.RS
.IP login 12
is the login name for a user or the remote computer,
.IP  sys
is the system name for a remote computer,
.IP c
is the optional
.I
call-back required
.R
flag,
.IP path-name
is a path-name prefix that is acceptable for
.I user.
.LP
.RE
.LP
The constraints are implemented as follows.
.RS
.IP [1]
When the program is obeying a command stored on the local machine,
.I MASTER
mode,
the path-names allowed are those given for the first line in the
.I USERFILE
that has a login name that matches the login name of the user
who entered the command.
If no such line is found, the first line with a
.I null
login name is used.
.IP [2]
When the program is responding to a command from a remote machine,
.I SLAVE
mode, the path-names allowed are those given for the first line
in the file that has the system name that matches the system name
of the remote machine.
If no such line is found, the first one with a
.I null
system name is used.
.IP [3]
When a remote computer logs in, the login name that
it uses must appear in the
.I USERFILE .
There may be several lines with the same login name but one of them must
either have the name of the remote system or must contain a
.I null
system name.
.IP [4]
If the line matched in ([3]) contains a ``c'',
the remote machine is called back before any transactions take place.
.RE
.LP
The line
.IP "" 12
u,m  /usr/xyz
.LP
allows machine
.I m
to login with name
.I u
and request the transfer of files whose names start with
``/usr/xyz''.
.LP
The line
.IP "" 12
dan,  /usr/dan
.LP
allows the ordinary user
.I dan
to issue commands for files whose name starts with
``/usr/dan''.
.LP
The lines
.IP "" 12
u,m /usr/xyz  /usr/spool
.br
u,  /usr/spool
.LP
allows any remote machine to login with name
.I u ,
but if its system name is not
.I m ,
it can only ask to transfer files whose names start with
``/usr/spool''.
.LP
The lines
.IP "" 12
root,  /
.br
,   /usr
.LP
allows any user to transfer files beginning with ``/usr''
but the user with login
.I root
can transfer any file.
.SH
L.sys
.LP
Each entry in this file represents one system
which can be called by the local uucp programs.
The fields are described below.
.RS
.SH
system name
.LP
The name of the remote system.
.SH
time
.LP
This is a string which indicates the days-of-week
and times-of-day when the system should
be called
(e.g. MoTuTh0800\-1730).
.LP
The day portion may be a list containing
some of
.IP
.I
Su Mo Tu We Th Fr Sa
.R
.LP
or it may be
.I Wk
for any week-day or
.I Any
for any day.
.LP
The time should be a range of times (e.g. 0800\-1230).
If no time portion is specified, any time
of day is assumed to be ok for the call.
.SH
device
.LP
This is either
.I ACU
or the hardwired device to be used for the call.
For the hardwired case, the last part of the
special file name is used (e.g. tty0).
.SH
speed
.LP
This is the line speed for the call (e.g. 300).
.SH
phone
.LP
The phone number is made up of an optional
alphabetic abbreviation and a numeric part.
The abbreviation is one which appears in the
.I L-dialcodes
file (e.g. mh5900, boston995\-9980).
.LP
For the hardwired devices, this field contains
the same string as used for the
.I device
field.
.SH
login
.LP
The login information is given as a series of
fields and subfields in the format
.IP
expect\ \ send\ 
.B [
expect\ \ send
.B ]
\ ...
.LP
where;
.I expect
is the string expected to be read and
.I send
is the string to be sent when the
.I expect
string is received.
.LP
The expect field may be made up of subfields
of the form
.IP
expect\fB[\fR\-send\-expect\fB]\fR...
.LP
where the
.I send
is sent if the prior
.I expect
is not successfully read
and the
.I expect
following the
.I send
is the next expected string.
.LP
There are two special names available to be sent
during the login sequence.
The string
.I EOT
will send an EOT character and the string
.I BREAK
will try to send a BREAK character.
(The
.I BREAK
character is simulated using line speed changes
and null characters and may not work on all
devices and/or systems.)
.RE
.LP
A typical entry in the L.sys file would be
.IP "" 6
sys Any ACU 300  mh7654 login uucp ssword: word
.LP
The expect algorithm looks at the last part of the
string as illustrated in the password field.
.RE
.NH
Administration
.LP
This section indicates some events and files which must be
administered for the
.I uucp
system.
Some administration can be accomplished by 
.I "shell files"
which can be initiated by
.I crontab
entries.
Others will require manual intervention.
Some sample 
.I "shell files"
are given toward the end of this section.
.SH
SQFILE \- sequence check file
.LP
This file is set up in the
.I program
directory and contains an entry for each remote
system with which you agree to perform conversation
sequence checks.
The initial entry is just the system name of
the remote system.
The first conversation will add two items to the line,
the conversation count, and the date/time of the most
resent conversation.
These items will be updated with each conversation.
If a sequence check fails, the entry will have to
be adjusted.
.SH
TM \- temporary data files
.LP
These files are created in the
.I spool
directory while files are being copied
from a remote machine.
Their names have the form
.IP "" 12
\fBTM\fR.pid.ddd
.LP
where
.I pid
is a process-id and
.I ddd
is a sequential three digit number starting at zero
for each invocation of
.I uucico
and incremented for each file received.

After the entire remote file is received, the
.I TM
file is moved/copied to the requested destination.
If processing is abnormally terminated or the
move/copy fails, the file will remain in the
spool directory.
.LP
The leftover files should be periodically removed;
the
.I uuclean
program is useful in this regard.
The command
.IP "" 12
uuclean\ \ \-pTM
.LP
will remove all
.I TM
files older than three days.
.SH
LOG \- log entry files
.LP
During execution of programs, individual
.I LOG
files are created in the
.I spool
directory with information about
queued requests, calls to remote systems,
execution of
.I uux
commands and file copy results.
These files should be combined into the
.I LOGFILE
by using the
.I uulog
program.
This program will put the new
.I LOG
files at the beginning of the existing
.I LOGFILE.
The command
.IP "" 12
uulog
.LP
will accomplish the merge.
Options are available to print some or all the
log entries after the files are merged.
The
.I LOGFILE
should be removed periodically
since it is copied each time new LOG
entries are put into the file.
.LP
The
.I LOG
files are created initially with mode 0222.
If the program which creates the file terminates normally,
it changes the
mode to 0666.
Aborted runs may leave the files with mode
0222 and the
.I uulog
program will not read or remove them.
To remove them, either use
.I rm ,
.I uuclean ,
or change the mode to 0666 and let
.I uulog
merge them with the
.I LOGFILE .
.SH
STST \- system status files
.LP
These files are created in the spool directory by the
.I uucico
program.
They contain information of failures such as login, dialup or
sequence check and will contain a
.I TALKING
status when to machines are conversing.
The form of the file name is
.IP
\fBSTST\fR.sys
.LP
where
.I sys
is the remote system name.
.LP
For ordinary failures (dialup, login), the file will prevent
repeated tries for about one hour.
For sequence check failures, the file must be removed before
any future attempts to converse with that remote system.
.LP
If the file is left due to an aborted run, it may contain a
.I TALKING
status.
In this case, the file must be removed before a conversation
is attempted.
.SH
LCK \- lock files
.LP
Lock files are created for each device in use (e.g. automatic calling
unit) and each system conversing.
This prevents duplicate conversations and multiple attempts to use the
same devices.
The form of the lock file name is
.IP "" 12
\fBLCK..\fRstr
.LP
where
.I str
is either a device or system name.
The files may be left in the spool directory if runs abort.
They will be ignored (reused) after a time of about 24 hours.
When runs abort and calls are desired before the time limit,
the lock files should be removed.
.SH
Shell Files
.LP
The
.I uucp
program will spool work and attempt to start the
.I uucico
program, but the starting of
.I uucico
will sometimes fail.
(No devices available, login failures etc.).
Therefore, the
.I uucico
program should be periodically started.
The command to start
.I uucico
can be put in a ``shell'' file with a command to merge
.I LOG
files and started by a crontab entry on an hourly basis.
The file could contain the commands
.IP
.I program /uulog
.br
.I program /uucico
\ \ \-r1
.LP
Note that the ``\-r1'' option is required to start the
.I uucico
program in
.I MASTER
mode.
.LP
Another shell file may be set up on a daily basis to remove
.I TM ,
.I ST
and
.I LCK
files
and
.I C.
or
.I D.
files for work which can not be accomplished for
reasons like bad phone number, login changes etc.
A shell file containing commands like
.IP
.I program /uuclean
\ \ \-pTM \-pC. \-pD.
.br
.I program /uuclean
\ \ \-pST \-pLCK \-n12
.LP
can be used.
Note the ``\-n12'' option causes the
.I ST
and
.I LCK
files older than 12 hours to be deleted.
The absence of the ``\-n'' option will use a three day time
limit.
.LP
A daily or weekly shell should also be created
to remove or save old
.I LOGFILE s.
A shell like
.IP
cp
.I spool /LOGFILE
\ \ 
.I spool /o.LOGFILE
.br
rm
.I spool /LOGFILE
.LP
can be used.
.SH
Login Entry
.LP
One or more logins should be set up for
.I uucp .
Each of the ``/etc/passwd'' entries should
have the
``\fIprogram\fR/uucico''
as the shell to be executed.
The login directory is not used, but if the system
has a special directory for use by the users for
sending or receiving file, it should as the
login entry.
The various logins are used in conjunction with the
.I USERFILE
to restrict file access.
Specifying the
.I shell
argument limits the login to the use of uucp
(
.I uucico )
only.
.SH
File Modes
.LP
It is suggested that the owner and file modes of various
programs and files be set as follows.
.LP
The programs
.I uucp ,
.I uux ,
.I uucico
and
.I uuxqt
should be owned by the
.I uucp
login with the ``setuid'' bit set and only execute
permissions (e.g. mode 04111).
This will prevent outsiders from modifying the programs
to get at a standard
.I shell
for the
.I uucp
logins.
.LP
The
.I L.sys ,
.I SQFILE
and the
.I USERFILE
which are put in the
.I program
directory should be owned by
the
.I uucp
login and set with mode 0400.
.SG MH-1273-DAN-unix