UUX(1P)                   POSIX Programmer's Manual                  UUX(1P)

PROLOG         top

       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.

NAME         top

       uux — remote command execution

SYNOPSIS         top

       uux [−jnp] command−string

DESCRIPTION         top

       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

        *  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.

OPTIONS         top

       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

OPERANDS         top

       The following operand shall be supported:

                 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.

STDIN         top

       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         top

       Input files shall be selected according to the contents of command-


       The following environment variables shall affect the execution of

       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

       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).

                 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.



STDOUT         top

       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>

STDERR         top

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES         top

       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.



EXIT STATUS         top

       The following exit values shall be returned:

        0    Successful completion.

       >0    An error occurred.



       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.

EXAMPLES         top

        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"

RATIONALE         top




SEE ALSO         top

       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

COPYRIGHT         top

       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 .

       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 .

IEEE/The Open Group                 2013                             UUX(1P)