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.

       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
       library  function  that returns a copy of the domainname field returned
       from a call to uname(2).

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

COLOPHON
       This page is part of release 4.16 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                             2017-09-15                  GETDOMAINNAME(2)