NAME¶
XkbListComponents - List of components for one or more component types
SYNOPSIS¶
XkbComponentListPtr XkbListComponents (Display
*dpy, unsigned int device_spec,
XkbComponentNamesPtr ptrns, int
*max_inout);
ARGUMENTS¶
- - dpy
- connection to X server
- - device_spec
- device ID, or XkbUseCoreKbd
- - ptrns
- namelist for components of interest
- - max_inout
- max # returned names, # left over
DESCRIPTION¶
You may ask the server for a list of components for one or more component types.
The request takes the form of a set of patterns, one pattern for each of the
component types, including a pattern for the complete keyboard description. To
obtain this list, use
XkbListComponents.
XkbListComponents queries the server for a list of component names
matching the patterns specified in
ptrns. It waits for a reply and
returns the matching component names in an XkbComponentListRec structure. When
you are done using the structure, you should free it using
XkbFreeComponentList. device_spec indicates a particular device in
which the caller is interested. A server is allowed (but not required) to
restrict its reply to portions of the database that are relevant for that
particular device.
ptrns is a pointer to an XkbComponentNamesRec. Each of the fields in
ptrns contains a pattern naming the components of interest. Each of the
patterns is composed of characters from the ISO Latin1 encoding, but can
contain only parentheses, the wildcard characters `?' and `*', and characters
permitted in a component class or member name. A pattern may be NULL, in which
case no components for that type is returned. Pattern matches with component
names are case sensitive. The `?' wildcard matches any single character,
except a left or right parenthesis; the `*' wildcard matches any number of
characters, except a left or right parenthesis. If an implementation allows
additional characters in a component class or member name other than those
required by the Xkb extension, the result of comparing one of the additional
characters to either of the wildcard characters is implementation-dependent.
If a pattern contains illegal characters, the illegal characters are ignored.
The matching process is carried out as if the illegal characters were omitted
from the pattern.
max_inout is used to throttle the amount of data passed to and from the
server. On input, it specifies the maximum number of names to be returned (the
total number of names in all component categories). Upon return from
XkbListComponents, max_inout contains the number of names that matched
the request but were not returned because of the limit.
Component Names
Component names have the form
class(member) where
class describes
a subset of the available components for a particular type and the optional
member identifies a specific component from that subset. For example,
the name "atlantis(acme)" for a symbols component might specify the
symbols used for the atlantis national keyboard layout by the vendor
"acme." Each class has an optional
default member -
references that specify a class but not a member refer to the default member
of the class, if one exists. Xkb places no constraints on the interpretation
of the class and member names used in component names.
The
class and
member names are both specified using characters
from the Latin-1 character set. Xkb implementations must accept all
alphanumeric characters, minus (`-') and underscore (`_') in class or member
names, and must not accept parentheses, plus, vertical bar, percent sign,
asterisk, question mark, or white space. The use of other characters is
implementation-dependent.
STRUCTURES¶
The component name patterns used to describe the request are passed to
XkbListComponents using an XkbComponentNamesRec structure. This
structure has no special allocation constraints or interrelationships with
other structures; allocate and free this structure using standard
malloc and
free calls or their equivalent:
typedef struct _XkbComponentNames {
char * keymap; /∗ keymap names */
char * keycodes; /∗ keycode names */
char * types; /∗ type names */
char * compat; /∗ compatibility map names */
char * symbols; /∗ symbol names */
char * geometry; /∗ geometry names */
} XkbComponentNamesRec, *XkbComponentNamesPtr;
XkbListComponents returns a pointer to an XkbComponentListRec:
typedef struct _XkbComponentList {
int num_keymaps; /∗ number of entries in keymap */
int num_keycodes; /∗ number of entries in keycodes */
int num_types; /∗ number of entries in types */
int num_compat; /∗ number of entries in compat */
int num_symbols; /∗ number of entries in symbols */
int num_geometry; /∗ number of entries in geometry;
XkbComponentNamePtr keymap; /∗ keymap names */
XkbComponentNamePtr keycodes; /∗ keycode names */
XkbComponentNamePtr types; /∗ type names */
XkbComponentNamePtr compat; /∗ compatibility map names */
XkbComponentNamePtr symbols; /∗ symbol names */
XkbComponentNamePtr geometry; /∗ geometry names */
} XkbComponentListRec, *XkbComponentListPtr;
typedef struct _XkbComponentName {
unsigned short flags; /∗ hints regarding component name */
char * name; /∗ name of component */
} XkbComponentNameRec, *XkbComponentNamePtr;
SEE ALSO¶
XkbFreeComponentList(3)
NOTES¶
Note that the structure used to specify patterns on input is an
XkbComponentNamesRec, and that used to hold the individual component names
upon return is an XkbComponentNameRec (no trailing `s' in Name).