setdomainname

GETDOMAINNAME(2)           Linux Programmer's Manual          GETDOMAINNAME(2)

NAME
       getdomainname, setdomainname - get/set NIS domain name

SYNOPSIS
       #include <unistd.h>

       int getdomainname(char *name, size_t len);
       int setdomainname(const char *name, size_t len);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       getdomainname(), setdomainname():
           Since glibc 2.21:
               _DEFAULT_SOURCE
           In glibc 2.19 and 2.20:
               _DEFAULT_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)
           Up to and including glibc 2.19:
               _BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)

DESCRIPTION
       These  functions are used to access or to change the NIS domain name of
       the host system.  More precisely, they operate on the NIS  domain  name
       associated with the calling process's UTS namespace.

       setdomainname()  sets the domain name to the value given in the charac-
       ter array name.  The len argument specifies  the  number  of  bytes  in
       name.  (Thus, name does not require a terminating null byte.)

       getdomainname()  returns the null-terminated domain name in the charac-
       ter array name, which has a length of len bytes.   If  the  null-termi-
       nated domain name requires more than len bytes, getdomainname() returns
       the first len bytes (glibc) or gives an error (libc).

RETURN VALUE
       On success, zero is returned.  On error, -1 is returned, and  errno  is
       set appropriately.

ERRORS
       setdomainname() can fail with the following errors:

       EFAULT name pointed outside of user address space.

       EINVAL len was negative or too large.

       EPERM  The caller did not have the CAP_SYS_ADMIN capability in the user
              namespace associated with its UTS namespace (see namespaces(7)).

       getdomainname() can fail with the following errors:

       EINVAL For getdomainname() under libc: name is NULL or name  is  longer
              than len bytes.

CONFORMING TO
       POSIX does not specify these calls.

NOTES
       Since  Linux  1.0,  the limit on the length of a domain name, including
       the terminating null byte, is 64 bytes.  In older  kernels,  it  was  8
       bytes.

       On  most  Linux  architectures  (including x86), there is no getdomain-
       name() system call; instead, glibc implements getdomainname() as a  li-
       brary  function  that  returns  a copy of the domainname field returned
       from a call to uname(2).

SEE ALSO
       gethostname(2), sethostname(2), uname(2), uts_namespaces(7)

COLOPHON
       This page is part of release 5.05 of the Linux  man-pages  project.   A
       description  of  the project, information about reporting bugs, and the
       latest    version    of    this    page,    can     be     found     at
       https://www.kernel.org/doc/man-pages/.

Linux                             2019-10-10                  GETDOMAINNAME(2)