uname(P)                                               uname(P)





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  speci-
       fied, symbols representing one or more system character-
       istics shall be written to the standard output. The for-
       mat  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 implementa-
              tion-defined communications network.

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

       -s     Write the name of the implementation of the oper-
              ating 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 internationaliza-
              tion 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  cate-
              gories.)

       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 mes-
              sages 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 writ-
       ten; all such symbols shall be written at the end of the
       line of output before the <newline>.

       If  options  are  specified to select different combina-
       tions of the symbols, only those symbols shall be  writ-
       ten,  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  writ-
              ten.

       >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  multi-
       ple 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, sep-
       arated by one or more <blank>s.

RATIONALE
       It was  suggested  that  this  utility  cannot  be  used
       portably  since the format of the symbols is implementa-
       tion-defined.  The  POSIX.1  working  group  could   not
       achieve  consensus  on  defining  these  formats  in the
       underlying uname() function, and there was  no  expecta-
       tion  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 sym-
       bols could be used for system log entries or for compar-
       ison 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  Operat-
       ing System Interface (POSIX), The Open Group Base Speci-
       fications Issue 6, Copyright (C) 2001-2003 by the Insti-
       tute  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.open-
       group.org/unix/online.html .



POSIX                         2003                     uname(P)
