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

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

       uname — return system name

SYNOPSIS         top

       uname [−amnrsv]

DESCRIPTION         top

       By default, the uname utility shall write the operating system name
       to standard output. When options are specified, symbols representing
       one or more system characteristics shall be written to the standard
       output. The format and contents of the symbols are implementation-
       defined. On systems conforming to the System Interfaces volume of
       POSIX.1‐2008, the symbols written shall be those supported by the
       uname() function as defined in the System Interfaces volume of
       POSIX.1‐2008.

OPTIONS         top

       The uname utility shall conform to the Base Definitions volume of
       POSIX.1‐2008, Section 12.2, Utility Syntax Guidelines.

       The following options shall be supported:

       −a        Behave as though all of the options −mnrsv were specified.

       −m        Write the name of the hardware type on which the system is
                 running to standard output.

       −n        Write the name of this node within an implementation-
                 defined communications network.

       −r        Write the current release level of the operating system
                 implementation.

       −s        Write the name of the implementation of the operating
                 system.

       −v        Write the current version level of this release of the
                 operating system implementation.

       If no options are specified, the uname utility shall write the
       operating system name, as if the −s option had been specified.

OPERANDS         top

       None.

STDIN         top

       Not used.

INPUT FILES         top

       None.

ENVIRONMENT VARIABLES         top

       The following environment variables shall affect the execution of
       uname:

       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.

ASYNCHRONOUS EVENTS         top

       Default.

STDOUT         top

       By default, the output shall be a single line of the following form:

           "%s\n", <sysname>

       If the −a option is specified, the output shall be a single line of
       the following form:

           "%s %s %s %s %s\n", <sysname>, <nodename>, <release>,
               <version>, <machine>

       Additional implementation-defined symbols may be written; all such
       symbols shall be written at the end of the line of output before the
       <newline>.

       If options are specified to select different combinations of the
       symbols, only those symbols shall be written, in the order shown
       above for the −a option. If a symbol is not selected for writing, its
       corresponding trailing <blank> characters also shall not be written.

STDERR         top

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES         top

       None.

EXTENDED DESCRIPTION         top

       None.

EXIT STATUS         top

       The following exit values shall be returned:

        0    The requested information was successfully written.

       >0    An error occurred.

CONSEQUENCES OF ERRORS         top

       Default.

       The following sections are informative.

APPLICATION USAGE         top

       Note that any of the symbols could include embedded <space>
       characters, which may affect parsing algorithms if multiple options
       are selected for output.

       The node name is typically a name that the system uses to identify
       itself for inter-system communication addressing.

EXAMPLES         top

       The following command:

           uname −sr

       writes the operating system name and release level, separated by one
       or more <blank> characters.

RATIONALE         top

       It was suggested that this utility cannot be used portably since the
       format of the symbols is implementation-defined. The POSIX.1 working
       group could not achieve consensus on defining these formats in the
       underlying uname() function, and there was no expectation that this
       volume of POSIX.1‐2008 would be any more successful. Some
       applications may still find this historical utility of value. For
       example, the symbols could be used for system log entries or for
       comparison with operator or user input.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       The Base Definitions volume of POSIX.1‐2008, Chapter 8, Environment
       Variables, Section 12.2, Utility Syntax Guidelines

       The System Interfaces volume of POSIX.1‐2008, uname(3p)

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 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                           UNAME(1P)