XAddHost(3X11)              X Version 11(Release 5)              XAddHost(3X11)


NAME
      XAddHost, XAddHosts, XListHosts, XRemoveHost, XRemoveHosts,
      XSetAccessControl, XEnableAccessControl, XDisableAccessControl,
      XHostAddress - control host access and host control structure

SYNTAX
      XAddHost(display, host)
            Display *display;
            XHostAddress *host;

      XAddHosts(display, hosts, num_hosts)
            Display *display;
            XHostAddress *hosts;
            int num_hosts;

      XHostAddress *XListHosts(display, nhosts_return, state_return)
            Display *display;
            int *nhosts_return;
            Bool *state_return;

      XRemoveHost(display, host)
            Display *display;
            XHostAddress *host;

      XRemoveHosts(display, hosts, num_hosts)
            Display *display;
            XHostAddress *hosts;
            int num_hosts;

      XSetAccessControl(display, mode)
            Display *display;
            int mode;

      XEnableAccessControl(display)
            Display *display;

      XDisableAccessControl(display)
            Display *display;

ARGUMENTS
      display   Specifies the connection to the X server.

      host      Specifies the host that is to be added or removed.

      hosts     Specifies each host that is to be added or removed.

      mode      Specifies the mode.  You can pass EnableAccess or
                DisableAccess.

      nhosts_return
                Returns the number of hosts currently in the access control
                list.


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      num_hosts Specifies the number of hosts.

      state_return
                Returns the state of the access control.

DESCRIPTION
      The XAddHost function adds the specified host to the access control list
      for that display.  The server must be on the same host as the client
      issuing the command, or a BadAccess error results.

      XAddHost can generate BadAccess and BadValue errors.

      The XAddHosts function adds each specified host to the access control
      list for that display.  The server must be on the same host as the client
      issuing the command, or a BadAccess error results.

      XAddHosts can generate BadAccess and BadValue errors.

      The XListHosts function returns the current access control list as well
      as whether the use of the list at connection setup was enabled or
      disabled.  XListHosts allows a program to find out what machines can make
      connections.  It also returns a pointer to a list of host structures that
      were allocated by the function. When no longer needed, this memory should
      be freed by calling XFree.

      The XRemoveHost function removes the specified host from the access
      control list for that display.  The server must be on the same host as
      the client process, or a BadAccess error results.  If you remove your
      machine from the access list, you can no longer connect to that server,
      and this operation cannot be reversed unless you reset the server.

      XRemoveHost can generate BadAccess and BadValue errors.

      The XRemoveHosts function removes each specified host from the access
      control list for that display. The X server must be on the same host as
      the client process, or a BadAccess error results.  If you remove your
      machine from the access list, you can no longer connect to that server,
      and this operation cannot be reversed unless you reset the server.

      XRemoveHosts can generate BadAccess and BadValue errors.

      The XSetAccessControl function either enables or disables the use of the
      access control list at each connection setup.

      XSetAccessControl can generate BadAccess and BadValue errors.

      The XEnableAccessControl function enables the use of the access control
      list at each connection setup.

      XEnableAccessControl can generate a BadAccess error.




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      The XDisableAccessControl function disables the use of the access control
      list at each connection setup.

      XDisableAccessControl can generate a BadAccess error.

STRUCTURES
      The XHostAddress structure contains:

      typedef struct {
           int family;              /* for example FamilyInternet */
           int length;              /* length of address, in bytes */
           char *address;           /* pointer to where to find the address */
      } XHostAddress;

      The family member specifies which protocol address family to use (for
      example, TCP/IP or DECnet) and can be FamilyInternet, FamilyDECnet, or
      FamilyChaos.  The length member specifies the length of the address in
      bytes.  The address member specifies a pointer to the address.

DIAGNOSTICS
      BadAccess A client attempted to modify the access control list from other
                than the local (or otherwise authorized) host.

      BadValue  Some numeric value falls outside the range of values accepted
                by the request.  Unless a specific range is specified for an
                argument, the full range defined by the argument's type is
                accepted.  Any argument defined as a set of alternatives can
                generate this error.

SEE ALSO
      XFree(3X11)
      Xlib - C Language X Interface






















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