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.
NAME
uname - 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 network.
The arrays release and version shall further identify the operating
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 IEEE Std 1003.1-2001 imple-
mented in the operating system. An application should instead depend on
_POSIX_VERSION and related constants defined in <unistd.h>.
This volume of IEEE Std 1003.1-2001 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 IEEE Std 1003.1-2001, <sys/utsname.h>
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(3P)