uux(1C) — BASIC NETWORKING COMMANDS

NAME

uux − UNIX-to-UNIX system command execution

SYNOPSIS

uux [ options ] command-string

DESCRIPTION

uux will gather zero or more files from various systems, execute a command on a specified system and then send standard output to a file on a specified system.

NOTE: For security reasons, most installations limit the list of commands executable on behalf of an incoming request from uux, permitting only the receipt of mail [see mail(1)]. Remote execution permissions are defined in /etc/uucp/Permissions.

The command-string is made up of one or more arguments that look like a shell command line, except that the command and filenames may be prefixed by system-name!. A null system-name is interpreted as the local system.

File names may be one of:

(1) a full path name;

(2) a path name preceded by ~xxx, where xxx is a login name on the specified system and is replaced by that user’s login directory;

(3) anything else is prefixed by the current directory.

As an example, the command

uux "!diff sys1!/home/dan/file1 sys2!/a4/dan/file2 > !~/dan/file.diff"

will get the file1 and file2 files from the sys1 and sys2 machines, execute a diff(1) command and put the results in file.diff in the local PUBDIR/dan/ directory. PUBDIR is a public directory defined in the uucp source. By default, this directory is /var/spool/uucppublic.

Any special shell characters such as <, >, ;, | should be quoted either by quoting the entire command-string, or quoting the special characters as individual arguments.

uux will attempt to get all appropriate files to the specified system where they will be processed. For files that are output files, the filename must be escaped using parentheses. For example, the command:

uux "a!cut -f1 b!/usr/file > c!/usr/file"

gets /usr/file from system b and sends it to system a performs a cut command on that file and sends the result of the cut command to system c.

uux will notify you if the requested command on the remote system was disallowed. This notification can be turned off by the −n option. The response comes by remote mail from the remote machine.

The following options are interpreted by uux:

− The standard input to uux is made the standard input to the command-string.

−aname Use name as the user job identification replacing the initiator user-ID. (Notification will be returned to user-ID name.)

−b Return whatever standard input was provided to the uux command if the exit status is non-zero.

−c Do not copy local file to the spool directory for transfer to the remote machine (default).

−C Force the copy of local files to the spool directory for transfer.

−ggrade grade can be either a single letter, number, or a string of alphanumeric characters defining a service grade. The uuglist(1C) command determines whether it is appropriate to use the single letter, number, or a string of alphanumeric characters as a service grade. The output from the uuglist command will be a list of service grades that are available or a message that says to use a single letter or number as a grade of service.

−j Output the job ID string on the standard output which is the job identification. This job identification can be used by uustat(1C) to obtain the status or terminate a job.

−n Do not notify the user if the command fails.

−p Same as −: The standard input to uux is made the standard input to the command-string.

−r Do not start the file transfer, just queue the job.

−sfile Report status of the transfer in file.

−xdebug_level
Produce debugging output on the standard output. debug_level is a number between 0 and 9; as it increases to 9, more detailed debugging information is given.

−z Send success notification to the user.

FILES

/var/spool/uucp spool directories

/etc/uucp/Permissions
remote execution permissions

/usr/lib/uucp/∗ other programs

/etc/uucp/∗ other data and programs

NOTES

Only the first command of a shell pipeline may have a system-name!. All other commands are executed on the system of the first command.

The use of the shell metacharacter ∗ will probably not do what you want it to do. The shell tokens << and >> are not implemented.

The execution of commands on remote systems takes place in an execution directory known to the uucp system. All files required for the execution will be put into this directory unless they already reside on that machine. Therefore, the
simple filename (without path or machine reference) must be unique within the uux request. The following command will not work:

uux "a!diff b!/home/dan/xyz c!/home/dan/xyz > !xyz.diff"

The following command will work if diff is a permitted command:

uux "a!diff a!/home/dan/xyz c!/home/dan/xyz > !xyz.diff"

Protected files and files that are in protected directories that are owned by the requester can be sent in commands using uux. However, if the requester is root, and the directory is not searchable by other, the request will fail.

INTERNATIONAL FUNCTIONS

uux can process characters from supplementary code sets.

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