selection(n)						       Tk Built-In Commands						      selection(n)

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NAME

       selection - Manipulate the X selection

SYNOPSIS

       selection option ?arg arg ...?
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DESCRIPTION

       This  command  provides	a  Tcl	interface  to the X selection mechanism and implements the full selection functionality described in the X
       Inter-Client Communication Conventions Manual (ICCCM).

       The first argument to selection determines the format of the rest of the arguments and the behavior of the command.   The  following  forms
       are currently supported:

       selection clear ?-displayof window? ?-selection selection?
	      If  selection exists anywhere on window's display, clear it so that no window owns the selection anymore.  Selection specifies the X
	      selection that should be cleared, and should be an atom name such as PRIMARY or CLIPBOARD; see the Inter-Client  Communication  Con-
	      ventions Manual for complete details.  Selection defaults to PRIMARY and window defaults to ``.''.  Returns an empty string.

       selection get ?-displayof window? ?-selection selection? ?-type type?
	      Retrieves  the  value  of  selection  from  window's  display  and returns it as a result.  Selection defaults to PRIMARY and window
	      defaults to ``.''.  Type specifies the form in which the selection is to be returned (the  desired  ``target''  for  conversion,	in
	      ICCCM  terminology),  and  should be an atom name such as STRING or FILE_NAME; see the Inter-Client Communication Conventions Manual
	      for complete details.  Type defaults to STRING.  The selection owner may choose to return the selection in any of several  different
	      representation formats, such as STRING, ATOM, INTEGER, etc. (this format is different than the selection type; see the ICCCM for all
	      the confusing details).  If the selection is returned in a non-string format, such as INTEGER or ATOM, the  selection  command  con-
	      verts  it  to  string format as a collection of fields separated by spaces: atoms are converted to their textual names, and anything
	      else is converted to hexadecimal integers.

       selection handle ?-selection selection? ?-type type? ?-format format? window command
	      Creates a handler for selection requests, such that command will be executed whenever selection  is  owned  by  window  and  someone
	      attempts to retrieve it in the form given by type (e.g. type is specified in the selection get command).	Selection defaults to PRI-
	      MARY, type defaults to STRING, and format defaults to STRING.  If command is an empty string then any existing handler  for  window,
	      type, and selection is removed.

	      When  selection  is requested, window is the selection owner, and type is the requested type, command will be executed as a Tcl com-
	      mand with two additional numbers appended to it (with space separators).	The two additional numbers are offset and maxChars:   off- |
	      set  specifies  a starting character position in the selection and maxChars gives the maximum number of characters to retrieve.  The |
	      command should return a value consisting of at most maxChars of the selection, starting at position offset.  For very  large  selec- |
	      tions (larger than maxChars) the selection will be retrieved using several invocations of command with increasing offset values.	If |
	      command returns a string whose length is less than maxChars, the return value is assumed to include all  of  the	remainder  of  the |
	      selection;  if the length of command's result is equal to maxChars then command will be invoked again, until it eventually returns a |
	      result shorter than maxChars.  The value of maxChars will always be relatively large (thousands of characters).

	      If command returns an error then the selection retrieval is rejected just as if the selection didn't exist at all.

	      The format argument specifies the representation that should be used to transmit the selection to the requester (the  second  column
	      of Table 2 of the ICCCM), and defaults to STRING.  If format is STRING, the selection is transmitted as 8-bit ASCII characters (i.e.
	      just in the form returned by command).  If format is ATOM, then the return value from command is divided into  fields  separated	by
	      white space;  each field is converted to its atom value, and the 32-bit atom value is transmitted instead of the atom name.  For any
	      other format, the return value from command is divided into fields separated by white space and each field is converted to a  32-bit
	      integer;	an array of integers is transmitted to the selection requester.

	      The  format  argument is needed only for compatibility with selection requesters that don't use Tk.  If Tk is being used to retrieve
	      the selection then the value is converted back to a string at the requesting end, so format is irrelevant.

       selection own ?-displayof window? ?-selection selection?

       selection own ?-command command? ?-selection selection? window
	      The first form of selection own returns the path name of the window in this application that owns selection on the display  contain-
	      ing  window,  or	an  empty  string  if  no window in this application owns the selection.  Selection defaults to PRIMARY and window
	      defaults to ``.''.

       The second form of selection own causes window to become the new owner of selection on window's	display,  returning  an  empty	string	as
       result.	The  existing  owner,  if any, is notified that it has lost the selection.  If command is specified, it is a Tcl script to execute
       when some other window claims ownership of the selection away from window.  Selection defaults to PRIMARY.

KEYWORDS

       clear, format, handler, ICCCM, own, selection, target, type

Tk									8.1							      selection(n)