uname(3p) — Linux manual page


UNAME(3P)               POSIX Programmer's Manual              UNAME(3P)

PROLOG         top

       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         top

       uname — get the name of the current system

SYNOPSIS         top

       #include <sys/utsname.h>

       int uname(struct utsname *name);

DESCRIPTION         top

       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

       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         top

       Upon successful completion, a non-negative value shall be
       returned.  Otherwise, -1 shall be returned and errno set to
       indicate the error.

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top



       The inclusion of the nodename member in this structure does not
       imply that it is sufficient information for interfacing to
       communications networks.

RATIONALE         top

       The values of the structure members are not constrained to have
       any relation to the version of this volume of POSIX.1‐2017
       implemented in the operating system. An application should
       instead depend on _POSIX_VERSION and related constants defined in

       This volume of POSIX.1‐2017 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 specification, the latter are not.



SEE ALSO         top

       The Base Definitions volume of POSIX.1‐2017, sys_utsname.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 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 .

       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.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group               2017                         UNAME(3P)

Pages that refer to this page: sys_utsname.h(0p)uname(1p)gethostname(3p)posix_trace_attr_destroy(3p)posix_trace_attr_getclockres(3p)