# uname

## 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.
    


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