Command(4) Kernel Interfaces Manual Command(4)
NAME
Command - Contains file transfer directions for the uucico daemon
SYNOPSIS
/usr/spool/uucp/LocalSystemName/C.SystemNamexxxx###
DESCRIPTION
Command (C.*) files contain the directions that the uucp uucico daemon follows when transferring files. The full pathname of a command
file is a form of the following: /usr/spool/uucp/SystemName/C.SystemNameNxxxx
/C.SystemName indicates the name of the remote system. N represents the grade of the work, and xxxx is the 4-digit hexadecimal transfer-
sequence number; for example, C.merlinCE01F.
The grade of the work specifies when the file is to be transmitted during a particular connection. The grade notation has the following
characteristics: It is a single number (0 to 9) or letter (A to Z, a to z). Lower sequence characters cause the file to be transmitted
earlier in the connection than do higher sequence characters. The number 0 (zero) is the highest grade, signifying the earliest transmit-
tal; z is the lowest grade, signifying the latest transmittal. The default grade is N.
A command file consists of a single line that includes the following kinds of information in the following order: An S (send) or R
(receive) notation. Note that a send command file is created by the uucp or uuto commands; a receive command file is created by the uux
command. The full pathname of the source file being transferred. A receive command file does not include this entry. The full pathname
of the destination file, or a pathname preceded by ~user (tilde user), where user is a login name on the specified system. Here, the tilde
is shorthand for the name of the user's home directory. The sender's login name. A list of the options, if any, included with the uucp,
uuto, or uux command. The name of the data file associated with the command file in the spooling directory. This field must contain an
entry. If one of the data-transfer commands (such as the uucp command with the default -c flag) does not create a data file, the uucp pro-
gram instead creates a placeholder with the name D.0 for send files, or dummy for receive files. The source file permissions code, speci-
fied as a 3-digit octal number (for example, 777). The login name of the user on the remote system who is to be notified when the transfer
is complete.
EXAMPLES
Examples of send command and receive command files follow.
Examples of Two Send Command Files
The send command file /usr/spool/uucp/venus/C.heraN1133, created with the uucp command, contains the following fields: S /u/betp/f1
/usr/spool/uucppublic/f2 betp .nL
-dC D.herale3655 777 jmp The fields are as follows: The S keyword denotes that the uucp command is sending the file. The
full pathname of the source file is /u/betp/f1. The full pathname of the destination is /usr/spool/uucppublic/f2, where /usr/spool/uucp-
public is the name of the uucp public spooling directory on the remote computer and f2 is the new name of the file.
Note that when the user's login ID is uucp, the destination name may be abbreviated as ~ uucp/f2. Here, the ~ (tilde) is a short-
hand way of designating the public directory. The person sending the file is betp. The sender entered the uucp command with the -C
flag, specifying that the uucp command program should transfer the file to the local spooling directory and create a data file for
it. (The -d flag, which specifies that the command should create any intermediate directories needed to copy the source file to the
destination, is the default.) The name of the Data (D.*) file is D.herale3655, which the uucp command assigns. The octal permis-
sions code is 777. On system hera, jmp is the login name of the user who is to be notified of the file arrival. The
/usr/spool/uucp/hera/C.zeusN3130 send command file, produced by the uuto command, is as follows:
S /u/betp/out ~/receive/msg/zeus betp .nL
-dcn D.0 777[4~ msg The S denotes that the /u/betp/out source file was sent to the receive/msg subdirectory in
the public spooling directory on system zeus by user betp. The uuto command used the default flags -d (create directories), -c
(transfer directly, no spooling directory or data file), and -n (notify recipient).
Note that the uuto command creates the receive/msg directory if it does not already exist. The D.0 notation is a placeholder, 777
is the permissions code, and msg is the recipient.
Example of a Receive Command File
The format of a receive command file is somewhat different from that of a send command file. When files required to run a specified com-
mand on a remote system are not present on that system, the uux command creates a receive command file.
For example, the following command produces the /usr/spool/uucp/zeus/C.heraR1e94 receive command file: uux - "diff /u/betp/out
hera!/u/betp/out2 > ~uucp/DF"
Note that the command in this example invokes the uux command to run a diff command on the local system, comparing file /u/betp/out
with file /u/betp/out2, which is stored on remote system hera. The output of the comparison is placed in file DF in the public
directory on the local system.
The actual receive command file looks like this: R /u/betp/out2 D.hera1e954fd betp - dummy 0666 betp
The R denotes a receive file. The uucico daemon, called by the uux command, gets the /u/betp/out2 file from system hera, and places
it in a data file called D.hera1e954fd for the transfer. Once the files are transferred, the uuxqt daemon executes the command on
the specified system. User betp issued the uux command with the - (dash) flag, which makes the standard input to the uux command
the standard input to the actual command string. No data file was created in the local spooling directory, so the uucp program uses
dummy as a placeholder. The permissions code is 666 (the uucp program prefixes the 3-digit octal code with a 0 [zero]), and user
betp is to be notified when the command finishes executing.
FILES
Describes access permissions for remote systems Describes accessible remote systems Contains uucp command, data, and execute files Contain
data to be transferred Contains transferred files
RELATED INFORMATION
Commands: uucp(1), uupick(1), uuto(1), uux(1), uuxqt(1), uudemon(4), cron(8), uucico(8), uusched(8) delim off
Command(4)