UNAME(3P) POSIX Programmer's Manual UNAME(3P)PROLOG
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.
NAMEuname — get the name of the current system
SYNOPSIS
#include <sys/utsname.h>
int uname(struct utsname *name);
DESCRIPTION
The uname() function shall store information identifying the current
system in the structure pointed to by name.
The uname() function uses the utsname structure defined in
<sys/utsname.h>.
The uname() function shall return a string naming the current system in
the character array sysname. Similarly, nodename shall contain the
name of this node within an implementation-defined communications net‐
work. The arrays release and version shall further identify the operat‐
ing system. The array machine shall contain a name that identifies the
hardware that the system is running on.
The format of each member is implementation-defined.
RETURN VALUE
Upon successful completion, a non-negative value shall be returned.
Otherwise, −1 shall be returned and errno set to indicate the error.
ERRORS
No errors are defined.
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
The inclusion of the nodename member in this structure does not imply
that it is sufficient information for interfacing to communications
networks.
RATIONALE
The values of the structure members are not constrained to have any
relation to the version of this volume of POSIX.1‐2008 implemented in
the operating system. An application should instead depend on
_POSIX_VERSION and related constants defined in <unistd.h>.
This volume of POSIX.1‐2008 does not define the sizes of the members of
the structure and permits them to be of different sizes, although most
implementations define them all to be the same size: eight bytes plus
one byte for the string terminator. That size for nodename is not
enough for use with many networks.
The uname() function originated in System III, System V, and related
implementations, and it does not exist in Version 7 or 4.3 BSD. The
values it returns are set at system compile time in those historical
implementations.
4.3 BSD has gethostname() and gethostid(), which return a symbolic name
and a numeric value, respectively. There are related sethostname() and
sethostid() functions that are used to set the values the other two
functions return. The former functions are included in this specifica‐
tion, the latter are not.
FUTURE DIRECTIONS
None.
SEE ALSO
The Base Definitions volume of POSIX.1‐2008, <sys_utsname.h>
COPYRIGHT
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 Electri‐
cal 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.ker‐
nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group 2013 UNAME(3P)
