XmbLookupString(3X11) XLIB FUNCTIONS XmbLookupString(3X11)NAME
XmbLookupString, XwcLookupString, Xutf8LookupString -
obtain composed input from an input method
SYNTAX
int XmbLookupString(ic, event, buffer_return,
bytes_buffer, keysym_return, status_return)
XIC ic;
XKeyPressedEvent *event;
char *buffer_return;
int bytes_buffer;
KeySym *keysym_return;
Status *status_return;
int XwcLookupString(ic, event, buffer_return,
bytes_buffer, keysym_return, status_return)
XIC ic;
XKeyPressedEvent *event;
wchar_t *buffer_return;
int wchars_buffer;
KeySym *keysym_return;
Status *status_return;
int Xutf8LookupString(ic, event, buffer_return,
bytes_buffer, keysym_return, status_return)
XIC ic;
XKeyPressedEvent *event;
char *buffer_return;
int bytes_buffer;
KeySym *keysym_return;
Status *status_return;
ARGUMENTS
buffer_return
Returns a multibyte string or wide character
string (if any) from the input method.
bytes_buffer
wchars_buffer
Specifies space available in the return buffer.
event Specifies the key event to be used.
ic Specifies the input context.
keysym_return
Returns the KeySym computed from the event if
this argument is not NULL.
status_return
Returns a value indicating what kind of data is
returned.
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XmbLookupString(3X11) XLIB FUNCTIONS XmbLookupString(3X11)DESCRIPTION
The XmbLookupString, XwcLookupString and Xutf8LookupString
functions return the string from the input method speci-
fied in the buffer_return argument. If no string is
returned, the buffer_return argument is unchanged.
The KeySym into which the KeyCode from the event was
mapped is returned in the keysym_return argument if it is
non-NULL and the status_return argument indicates that a
KeySym was returned. If both a string and a KeySym are
returned, the KeySym value does not necessarily correspond
to the string returned.
XmbLookupString and Xutf8LookupString return the length of
the string in bytes, and XwcLookupString returns the
length of the string in characters. Both XmbLookupString
and XwcLookupString return text in the encoding of the
locale bound to the input method of the specified input
context, and Xutf8LookupString returns text in UTF-8
encoding.
Each string returned by XmbLookupString and XwcLookup-
String begins in the initial state of the encoding of the
locale (if the encoding of the locale is state-dependent).
Note
(R)To ensure proper input processing, it is
essential that the client pass only KeyPress
events to XmbLookupString, XwcLookupString and
Xutf8LookupString. Their behavior when a client
passes a KeyRelease event is undefined.
Clients should check the status_return argument before
using the other returned values. These three functions
each return a value to status_return that indicates what
has been returned in the other arguments. The possible
values returned are:
XBufferOverflow The input string to be returned is too
large for the supplied buffer_return. The
required size (for XmbLookupString,
Xutf8LookupString in bytes; for XwcLookup-
String in characters) is returned as the
value of the function, and the contents of
buffer_return and keysym_return are not
modified. The client should recall the
function with the same event and a buffer
of adequate size to obtain the string.
XLookupNone No consistent input has been composed so
far. The contents of buffer_return and
keysym_return are not modified, and the
function returns zero.
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XmbLookupString(3X11) XLIB FUNCTIONS XmbLookupString(3X11)
XLookupChars Some input characters have been composed.
They are placed in the buffer_return argu-
ment, using the encoding described above,
and the string length is returned as the
value of the function. The content of the
keysym_return argument is not modified.
XLookupKeySym A KeySym has been returned instead of a
string and is returned in keysym_return.
The content of the buffer_return argument
is not modified, and the function returns
zero.
XLookupBoth Both a KeySym and a string are returned;
XLookupChars and XLookupKeySym occur simul-
taneously.
It does not make any difference if the input context
passed as an argument to XmbLookupString, XwcLookupString
and Xutf8LookupString is the one currently in possession
of the focus or not. Input may have been composed within
an input context before it lost the focus, and that input
may be returned on subsequent calls to XmbLookupString,
XwcLookupString or Xutf8LookupString even though it does
not have any more keyboard focus.
The function Xutf8LookupString is an XFree86 extension
introduced in XFree86 4.0.2. Its presence is indicated by
the macro X_HAVE_UTF8_STRING.
SEE ALSOXLookupKeysym(3X11)
Xlib - C Language X Interface
X Version 11 Release 6.4 3