XAddHost(3X11)      X Version 11 (Release 4)       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;


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  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.

       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


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       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.

       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:



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       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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