NAME

       uname - return system name

SYNOPSIS

       uname [-snrvma]

DESCRIPTION

       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 IEEE Std 1003.1-2001, the symbols written shall be  those  supported  by  the
       uname() function as defined in the System Interfaces volume of IEEE Std 1003.1-2001.

OPTIONS

       The  uname  utility  shall  conform to the Base Definitions volume of IEEE Std 1003.1-2001, 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

       None.

STDIN

       Not used.

INPUT FILES

       None.

ENVIRONMENT VARIABLES

       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 IEEE Std 1003.1-2001, 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

       Default.

STDOUT

       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>s also shall not be written.

STDERR

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES

       None.

EXTENDED DESCRIPTION

       None.

EXIT STATUS

       The following exit values shall be returned:

        0     The requested information was successfully written.

       >0     An error occurred.

CONSEQUENCES OF ERRORS

       Default.

       The following sections are informative.

APPLICATION USAGE

       Note that any of the symbols could include embedded <space>s, 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

       The following command:

              uname -sr

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

RATIONALE

       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 IEEE Std 1003.1-2001
       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

       None.

SEE ALSO

       The System Interfaces volume of IEEE Std 1003.1-2001, uname()

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers,
       Inc and The Open Group. 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.opengroup.org/unix/online.html .

IEEE/The Open Group                                   2003                                              UNAME(P)