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.
The following environment variables shall affect the execution of uname:
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.)
If set to a non-empty string value, override the values of
all the other internationalization variables.
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.
Determine the location of message catalogs for the
processing of LC_MESSAGES.
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.
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.
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.
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