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