Provided by: libx11-doc_1.4.99.1-0ubuntu2_all bug

NAME

       XmbLookupString, XwcLookupString, Xutf8LookupString - obtain composed input from an input
       method

SYNTAX

       int XmbLookupString(XIC ic, XKeyPressedEvent *event, char *buffer_return, int
              bytes_buffer, KeySym *keysym_return, Status *status_return);

       int XwcLookupString(XIC ic, XKeyPressedEvent *event, wchar_t *buffer_return, int
              wchars_buffer, KeySym *keysym_return, Status *status_return);

       int Xutf8LookupString(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.

DESCRIPTION

       The XmbLookupString, XwcLookupString and Xutf8LookupString functions return the string
       from the input method specified 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 XwcLookupString begins in the initial state of
       the encoding of the locale (if the encoding of the locale is state-dependent).

                                                  Note

            ®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
                         XwcLookupString 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.
       XLookupChars      Some input characters have been composed.
                         They are placed in the buffer_return
                         argument, 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
                         simultaneously.

       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 extension introduced by The XFree86 Project, Inc. in
       their 4.0.2 release. Its presence is indicated by the macro X_HAVE_UTF8_STRING.

SEE ALSO

       XLookupKeysym(3), Compose(5)
       Xlib - C Language X Interface