XAddHost(3) XLIB FUNCTIONS XAddHost(3)
NAME
XAddHost, XAddHosts, XListHosts, XRemoveHost, XRemoveHosts, XSetAccess-
Control, XEnableAccessControl, XDisableAccessControl, XHostAddress,
XServerInterpretedAddress - control host access and host control struc-
ture
SYNTAX
int XAddHost(Display *display, XHostAddress *host);
int XAddHosts(Display *display, XHostAddress *hosts, int num_hosts);
XHostAddress *XListHosts(Display *display, int *nhosts_return, Bool
*state_return);
int XRemoveHost(Display *display, XHostAddress *host);
int XRemoveHosts(Display *display, XHostAddress *hosts, int num_hosts);
int XSetAccessControl(Display *display, int mode);
int XEnableAccessControl(Display *display);
int XDisableAccessControl(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 DisableAc-
cess.
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 is-
suing 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 dis-
abled. 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 con-
trol 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 ma-
chine 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 con-
trol 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, FamilyInternet6,
FamilyServerInterpreted, FamilyDECnet, or FamilyChaos. The length mem-
ber specifies the length of the address in bytes. The address member
specifies a pointer to the address.
For the ServerInterpreted family, the length is ignored and the address
member is a pointer to a XServerInterpretedAddress structure which con-
tains:
typedef struct {
int typelength; /* length of type string, in bytes */
int valuelength; /* length of value string, in bytes */
char *type; /* pointer to where to find the type string */
char *value; /* pointer to where to find the address */
} XServerInterpretedAddress;
The type and value members point to strings representing the type and
value of the server interpreted entry. These strings may not be NULL-
terminated so care should be used when accessing them. The typelength
and valuelength members specify the length in byte of the type and value
strings.
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 ac-
cepted. Any argument defined as a set of alternatives can
generate this error.
SEE ALSO
XFree(3)
Xlib - C Language X Interface
X Version 11 libX11 1.8.12 XAddHost(3)
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