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 POSIX.1‐2017 implemented in the operating system. An application
       should instead depend on _POSIX_VERSION and related constants defined in <unistd.h>.

       This volume of POSIX.1‐2017 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.

FUTURE DIRECTIONS

       None.

SEE ALSO

       The Base Definitions volume of POSIX.1‐2017, <sys_utsname.h>

COPYRIGHT

       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 .