Minix Man Pages

home | help
x minix x
x minixx
GAI.CONF(5)                Linux Programmer's Manual               GAI.CONF(5)

NAME
       gai.conf - getaddrinfo(3) configuration file

DESCRIPTION
       A  call  to getaddrinfo(3) might return multiple answers.  According to
       RFC 3484 these answers must be sorted so that the answer with the high-
       est  success  rate is first in the list.  The RFC provides an algorithm
       for the sorting.  The static rules are  not  always  adequate,  though.
       For  this  reason,  the  RFC  also  requires that system administrators
       should have the possibility to dynamically change the sorting.  For the
       glibc implementation, this can be achieved with the /etc/gai.conf file.

       Each  line  in the configuration file consists of a keyword and its pa-
       rameters.  White spaces in any place are ignored.  Lines starting  with
       '#' are comments and are ignored.

       The keywords currently recognized are:

       label netmask precedence
              The value is added to the label table used in the RFC 3484 sort-
              ing.  If any label definition is present  in  the  configuration
              file,  the default table is not used.  All the label definitions
              of the default table which are to be maintained have to  be  du-
              plicated.  Following the keyword, the line has to contain a net-
              work mask and a precedence value.

       precedence netmask precedence
              This keyword is similar to label, but instead the value is added
              to  the  precedence table as specified in RFC 3484.  Once again,
              the presence of a single precedence line  in  the  configuration
              file causes the default table to not be used.

       reload <yes|no>
              This  keyword controls whether a process checks whether the con-
              figuration file has been changed since  the  last  time  it  was
              read.   If  the  value is "yes", the file is reread.  This might
              cause problems in multithreaded applications and is generally  a
              bad idea.  The default is "no".

       scopev4 mask value
              Add  another  rule to the RFC 3484 scope table for IPv4 address.
              By default, the scope IDs described in section 3.2  in  RFC 3438
              are  used.  Changing these defaults should hardly ever be neces-
              sary.

FILES
       /etc/gai.conf

VERSIONS
       The gai.conf file is supported by glibc since version 2.5.

EXAMPLE
       The default table according to RFC 3484 would  be  specified  with  the
       following configuration file:

           label  ::1/128       0
           label  ::/0          1
           label  2002::/16     2
           label ::/96          3
           label ::ffff:0:0/96  4
           precedence  ::1/128       50
           precedence  ::/0          40
           precedence  2002::/16     30
           precedence ::/96          20
           precedence ::ffff:0:0/96  10

SEE ALSO
       getaddrinfo(3), RFC 3484

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                             2016-03-15                       GAI.CONF(5)
NAME | DESCRIPTION | FILES | VERSIONS | EXAMPLE | SEE ALSO | COLOPHON