 |
Index for
Section 4 |
|
 |
Alphabetical
listing for E |
|
 |
Bottom of
page |
|
Execute(4)
NAME
Execute - Contains instructions for running commands that require the
resources of a remote system
SYNOPSIS
/usr/spool/uucp/SystemName/X.RemoteSystemNxxxx
DESCRIPTION
The Execute (X.*) files contain instructions for running uucp commands that
require the resources of a remote system. They are created by the uux
command. The full pathname of a uux command execute file is a form of the
following:
/usr/spool/uucp/SystemName/X.RemoteSystemNxxxx
where the SystemName directory is named for the local computer and the
RemoteSystem directory is named for the remote system. The N character
represents the grade of the work, and the xxxx notation is the 4-digit
hexadecimal transfer-sequence number; for example, X.zeusN2121.
Note that the grade of the work specifies when the file is to be
transmitted during a particular connection. The grade notation 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 transmittal; z is the lowest grade, signifying the latest
transmittal. The default grade is N.
Standard Entries in an Execute File
An execute file consists of several lines, each with an identification
character and one or more entries:
Line Format and Description
User Line
U UserName SystemName
Specifies the login name of the user issuing the uux command and
the name of the system from which the command was issued.
Error Status Line
N or Z
Indicates the error status.
The N character means that a failure message is not sent to the
user issuing the uux command if the specified command does not
execute successfully on the remote system.
The Z character means that a failure message is sent to the user
issuing the uux command if the specified command does not execute
successfully on the remote system.
Requester's Name
R UserName
Specifies the login ID of the user requesting the remote command
execution.
Required File Line
F FileName
Contains the names of the files required to execute the specified
command on the remote system. The FileName parameter can be either
the complete pathname of the file, including the unique
transmission name assigned by the uucp program, or simply the
transmission name without any path information.
The Required File Line can contain zero or more filenames. The
uuxqt daemon checks for the existence of all listed files before
running the specified command.
Standard Input Line
I FileName
Specifies the standard input to be used.
The standard input is either specified by a < (less than) symbol in
the command string, or is inherited from the standard input of the
uux command if that command was issued with the - (dash) flag. If
standard input is specified, it also is listed in an F (Required
File) line. If standard input is not specified, the uucp program
uses the /dev/null device file.
Standard Output Line
O FileName SystemName
Specifies the names of the file and system that are to receive
standard output from the execution of the command. Standard output
is specified by a > (greater than) symbol within the command
string. (The >> sequence is not valid in uux commands.) As was the
case with standard input, if standard output is not specified, the
uucp program uses the /dev/null device file.
Command Line
C CommandString
This is the command string that the user requests to be run on the
specified system. The uucp program checks the
/usr/lib/uucp/Permissions file on the designated computer to see
whether the login ID can run the command on that system. All
required files go to the execute file directory, usually
/usr/spool/uucp/.Xqtdir. After execution, the standard output is
sent to the requested location
EXAMPLES
1. User fong on local system zeus enters the following command:
uux - "diff /u/fong/out hera!/u/fong/out2 > ~uucp/DF"
This invokes the uux command to run a diff command on the local
system, comparing file /u/fong/out with file /u/fong/out2, which is
stored on remote system hera. The output of the comparison is placed
in the DF file in the public directory on the local system.
This command produced the /usr/spool/uucp/hera/X.zeusN212F execute
file, which contains the following information:
U fong zeus
# return status on failure
Z
# return address for status or input return
R fong
F /usr/spool/uucp/hera/D.herale954fd out2
O ~uucp/DF zeus
C diff /u/fong/out out2
The user line identifies user fong on system zeus. The error status
line indicates that fong will receive a failure status message if the
diff command fails to execute. The requester is fong, and the file
required to execute the command is the following data file:
/usr/spool/uucp/hera/D.herale954fd out2
The output of the command is to be written to the public directory on
system zeus with the filename DF. (Remember that ~uucp is the
shorthand way of specifying the public directory.) The final line is
the command string that user fong entered with the uux command.
2. The following is another example of an execute file:
U uucp hera
# don't return status on failure
N
# return address for status or input return
R uucp
F D.hera5eb7f7b
I D.hera5eb7f7b
C rmail fong
This indicates that user uucp on system hera is sending mail to user
fong, who is also working on system hera.
FILES
/usr/lib/uucp/Permissions
Describes access permissions for remote systems
/usr/lib/uucp/Systems
Describes accessible remote systems
/usr/spool/uucp/SystemName/*
Contains uucp command, data, and execute files
/usr/spool/uucp/SystemName/C.*
Contain instructions for transfers
/usr/spool/uucp/.Xqtdir/*
Contains lists of commands that remote systems are permitted to execute
/usr/spool/uucppublic/*
Contains files that have been transferred
SEE ALSO
Daemons: uuxqt
Commands: diff(1), uux(1)
|
Index for
Section 4 |
|
|
Alphabetical
listing for E |
|
 |
Top of
page |
|