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PROLOG | NAME | SYNOPSIS | DESCRIPTION | OPTIONS | OPERANDS | STDIN | INPUT FILES | ENVIRONMENT VARIABLES | ASYNCHRONOUS EVENTS | STDOUT | STDERR | OUTPUT FILES | EXTENDED DESCRIPTION | EXIT STATUS | CONSEQUENCES OF ERRORS | APPLICATION USAGE | EXAMPLES | RATIONALE | FUTURE DIRECTIONS | SEE ALSO | COPYRIGHT |
UUX(1P) POSIX Programmer's Manual UUX(1P)
This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
uux — remote command execution
uux [−jnp] command−string
The uux utility shall gather zero or more files from various systems,
execute a shell pipeline (see Section 2.9, Shell Commands) on a
specified system, and then send the standard output of the command to
a file on a specified system. Only the first command of a pipeline
can have a system-name! prefix. All other commands in the pipeline
shall be executed on the system of the first command.
The following restrictions are applicable to the shell pipeline
processed by uux:
* In gathering files from different systems, pathname expansion
shall not be performed by uux. Thus, a request such as:
uux "c99 remsys!~/*.c"
would attempt to copy the file named literally *.c to the local
system.
* The redirection operators ">>", "<<", ">|", and ">&" shall not be
accepted. Any use of these redirection operators shall cause this
utility to write an error message describing the problem and exit
with a non-zero exit status.
* The reserved word ! cannot be used at the head of the pipeline
to modify the exit status. (See the command-string operand
description below.)
* Alias substitution shall not be performed.
A filename can be specified as for uucp; it can be an absolute
pathname, a pathname preceded by ~name (which is replaced by the
corresponding login directory), a pathname specified as ~/dest (dest
is prefixed by the public directory called PUBDIR; the actual
location of PUBDIR is implementation-defined), or a simple filename
(which is prefixed by uux with the current directory). See uucp(1p)
for the details.
The execution of commands on remote systems shall take place in an
execution directory known to the uucp system. All files required for
the execution shall be put into this directory unless they already
reside on that machine. Therefore, the application shall ensure that
non-local filenames (without path or machine reference) are unique
within the uux request.
The uux utility shall attempt to get all files to the execution
system. For files that are output files, the application shall ensure
that the filename is escaped using parentheses.
The remote system shall notify the user by mail if the requested
command on the remote system was disallowed or the files were not
accessible. This notification can be turned off by the −n option.
Typical implementations of this utility require a communications line
configured to use the Base Definitions volume of POSIX.1‐2008,
Chapter 11, General Terminal Interface, but other communications
means may be used. On systems where there are no available
communications means (either temporarily or permanently), this
utility shall write an error message describing the problem and exit
with a non-zero exit status.
The uux utility cannot guarantee support for all character encodings
in all circumstances. For example, transmission data may be
restricted to 7 bits by the underlying network, 8-bit data and
filenames need not be portable to non-internationalized systems, and
so on. Under these circumstances, it is recommended that only
characters defined in the ISO/IEC 646:1991 standard International
Reference Version (equivalent to ASCII) 7-bit range of characters be
used and that only characters defined in the portable filename
character set be used for naming files.
The uux utility shall conform to the Base Definitions volume of
POSIX.1‐2008, Section 12.2, Utility Syntax Guidelines.
The following options shall be supported:
−j Write the job identification string to standard output.
This job identification can be used by uustat to obtain the
status or terminate a job.
−n Do not notify the user if the command fails.
−p Make the standard input to uux the standard input to the
command-string.
The following operand shall be supported:
command-string
A string made up of one or more arguments that are similar
to normal command arguments, except that the command and
any filenames can be prefixed by system-name!. A null
system-name shall be interpreted as the local system.
The standard input shall not be used unless the '−' or −p option is
specified; in those cases, the standard input shall be made the
standard input of the command-string.
Input files shall be selected according to the contents of command-
string.
The following environment variables shall affect the execution of
uux:
LANG Provide a default value for the internationalization
variables that are unset or null. (See the Base Definitions
volume of POSIX.1‐2008, Section 8.2, Internationalization
Variables for the precedence of internationalization
variables used to determine the values of locale
categories.)
LC_ALL If set to a non-empty string value, override the values of
all the other internationalization variables.
LC_CTYPE Determine the locale for the interpretation of sequences of
bytes of text data as characters (for example, single-byte
as opposed to multi-byte characters in arguments).
LC_MESSAGES
Determine the locale that should be used to affect the
format and contents of diagnostic messages written to
standard error.
NLSPATH Determine the location of message catalogs for the
processing of LC_MESSAGES.
Default.
The standard output shall not be used unless the −j option is
specified; in that case, the job identification string shall be
written to standard output in the following format:
"%s\n", <jobid>
The standard error shall be used only for diagnostic messages.
Output files shall be created or written, or both, according to the
contents of command-string.
If −n is not used, mail files shall be modified following any command
or file-access failures on the remote system.
None.
The following exit values shall be returned:
0 Successful completion.
>0 An error occurred.
Default.
The following sections are informative.
This utility is part of the UUCP Utilities option and need not be
supported by all implementations.
Note that, for security reasons, many installations limit the list of
commands executable on behalf of an incoming request from uux. Many
sites permit little more than the receipt of mail via uux.
Any characters special to the command interpreter should be quoted
either by quoting the entire command-string or quoting the special
characters as individual arguments.
As noted in uucp, shell pattern matching notation characters
appearing in pathnames are expanded on the appropriate local system.
This is done under the control of local settings of LC_COLLATE and
LC_CTYPE. Thus, care should be taken when using bracketed filename
patterns, as collation and typing rules may vary from one system to
another. Also be aware that certain types of expression (that is,
equivalence classes, character classes, and collating symbols) need
not be supported on non-internationalized systems.
1. The following command gets file1 from system a and file2 from
system b, executes diff on the local system, and puts the results
in file.diff in the local PUBDIR directory. (PUBDIR is the uucp
public directory on the local system.)
uux "!diff a!/usr/file1 b!/a4/file2 >!~/file.diff"
2. The following command fails because uux places all files copied
to a system in the same working directory. Although the files
xyz are from two different systems, their filenames are the same
and conflict.
uux "!diff a!/usr1/xyz b!/usr2/xyz >!~/xyz.diff"
3. The following command succeeds (assuming diff is permitted on
system a) because the file local to system a is not copied to the
working directory, and hence does not conflict with the file from
system c.
uux "a!diff a!/usr/xyz c!/usr/xyz >!~/xyz.diff"
None.
None.
Chapter 2, Shell Command Language, uucp(1p), uuencode(1p), uustat(1p)
The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment
Variables, Chapter 11, General Terminal Interface, Section 12.2,
Utility Syntax Guidelines
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) In the event of any discrepancy between this version and
the original IEEE and The Open Group Standard, the original IEEE and
The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 UUX(1P)
Pages that refer to this page: uucp(1p)