[OpenSPARC-T2-DV] / tools / src / nas,5.n2.os.2 / lib / python / man / man3 / Tk_DeleteSelHandler.3

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'\" Copyright (c) 1990-1994 The Regents of the University of California.
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'\" .OP cmdName dbName dbClass
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See the \\fBoptions\\fR manual entry for details on the standard options.
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.TH Tk_CreateSelHandler 3 4.0 Tk "Tk Library Procedures"
.BS
.SH NAME
Tk_CreateSelHandler, Tk_DeleteSelHandler \- arrange to handle requests for a selection
.SH SYNOPSIS
.nf
\fB#include <tk.h>\fR
.sp
\fBTk_CreateSelHandler\fR(\fItkwin, selection, target, proc, clientData, format\fR)
.sp
\fBTk_DeleteSelHandler\fR(\fItkwin, selection, target\fR)
.SH ARGUMENTS
.AS Tk_SelectionProc clientData
.AP Tk_Window tkwin in
Window for which \fIproc\fR will provide selection information.
.AP Atom selection in
The name of the selection for which \fIproc\fR will provide
selection information.
.AP Atom target in
Form in which \fIproc\fR can provide the selection (e.g. STRING
or FILE_NAME).  Corresponds to \fItype\fR arguments in \fBselection\fR
commands.
.AP Tk_SelectionProc *proc in
Procedure to invoke whenever the selection is owned by \fItkwin\fR
and the selection contents are requested in the format given by
\fItarget\fR.
.AP ClientData clientData in
Arbitrary one-word value to pass to \fIproc\fR.
.AP Atom format in
If the selection requestor isn't in this process, \fIformat\fR determines
the representation used to transmit the selection to its
requestor.
.BE

.SH DESCRIPTION
.PP
\fBTk_CreateSelHandler\fR arranges for a particular procedure
(\fIproc\fR) to be called whenever \fIselection\fR is owned by
\fItkwin\fR and the selection contents are requested in the
form given by \fItarget\fR. 
\fITarget\fR should be one of
the entries defined in the left column of Table 2 of the
X Inter-Client Communication Conventions Manual (ICCCM) or
any other form in which an application is willing to present
the selection.  The most common form is STRING.
.PP
\fIProc\fR should have arguments and result that match the
type \fBTk_SelectionProc\fR:
.CS
typedef int Tk_SelectionProc(
	ClientData \fIclientData\fR,
	int \fIoffset\fR,
	char *\fIbuffer\fR,
	int \fImaxBytes\fR);
.CE
The \fIclientData\fR parameter to \fIproc\fR is a copy of the
\fIclientData\fR argument given to \fBTk_CreateSelHandler\fR.
Typically, \fIclientData\fR points to a data
structure containing application-specific information that is
needed to retrieve the selection.  \fIOffset\fR specifies an
offset position into the selection, \fIbuffer\fR specifies a
location at which to copy information about the selection, and
\fImaxBytes\fR specifies the amount of space available at
\fIbuffer\fR.  \fIProc\fR should place a NULL-terminated string
at \fIbuffer\fR containing \fImaxBytes\fR or fewer characters
(not including the terminating NULL), and it should return a
count of the number of non-NULL characters stored at
\fIbuffer\fR.  If the selection no longer exists (e.g. it once
existed but the user deleted the range of characters containing
it), then \fIproc\fR should return -1.
.PP
When transferring large selections, Tk will break them up into
smaller pieces (typically a few thousand bytes each) for more
efficient transmission.  It will do this by calling \fIproc\fR
one or more times, using successively higher values of \fIoffset\fR
to retrieve successive portions of the selection.  If \fIproc\fR
returns a count less than \fImaxBytes\fR it means that the entire
remainder of the selection has been returned.  If \fIproc\fR's return
value is \fImaxBytes\fR it means there may be additional information
in the selection, so Tk must make another call to \fIproc\fR to
retrieve the next portion.
.PP
\fIProc\fR always returns selection information in the form of a
character string.  However, the ICCCM allows for information to
be transmitted from the selection owner to the selection requestor
in any of several formats, such as a string, an array of atoms, an
array of integers, etc.  The \fIformat\fR argument to
\fBTk_CreateSelHandler\fR indicates what format should be used to
transmit the selection to its requestor (see the middle column of
Table 2 of the ICCCM for examples).  If \fIformat\fR is not
STRING, then Tk will take the value returned by \fIproc\fR and divided
it into fields separated by white space.  If \fIformat\fR is ATOM,
then Tk will return the selection as an array of atoms, with each
field in \fIproc\fR's result treated as the name of one atom.  For
any other value of \fIformat\fR, Tk will return the selection as an
array of 32-bit values where each field of \fIproc\fR's result is
treated as a number and translated to a 32-bit value.  In any event,
the \fIformat\fR atom is returned to the selection requestor along
with the contents of the selection.
.PP
If \fBTk_CreateSelHandler\fR is called when there already exists a
handler for \fIselection\fR and \fItarget\fR on \fItkwin\fR, then the
existing handler is replaced with a new one.
.PP
\fBTk_DeleteSelHandler\fR removes the handler given by \fItkwin\fR,
\fIselection\fR, and \fItarget\fR, if such a handler exists.
If there is no such handler then it has no effect.

.SH KEYWORDS
format, handler, selection, target
Commit	Line	Data
86530b38 AT	1	'\"
	2	'\" Copyright (c) 1990-1994 The Regents of the University of California.
	3	'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
	4	'\"
	5	'\" See the file "license.terms" for information on usage and redistribution
	6	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	7	'\"
	8	'\" RCS: @(#) $Id: CrtSelHdlr.3,v 1.2 1998/09/14 18:22:47 stanton Exp $
	9	'\"
	10	'\" The definitions below are for supplemental macros used in Tcl/Tk
	11	'\" manual entries.
	12	'\"
	13	'\" .AP type name in/out ?indent?
	14	'\" Start paragraph describing an argument to a library procedure.
	15	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	16	'\" or "in/out" to describe whether procedure reads or modifies arg,
	17	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	18	'\" needed; use .AS below instead)
	19	'\"
	20	'\" .AS ?type? ?name?
	21	'\" Give maximum sizes of arguments for setting tab stops. Type and
	22	'\" name are examples of largest possible arguments that will be passed
	23	'\" to .AP later. If args are omitted, default tab stops are used.
	24	'\"
	25	'\" .BS
	26	'\" Start box enclosure. From here until next .BE, everything will be
	27	'\" enclosed in one large box.
	28	'\"
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	56	'\" options follow on successive lines, in four columns separated
	57	'\" by tabs.
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	60	'\" End of list of standard options for a Tk widget.
	61	'\"
	62	'\" .OP cmdName dbName dbClass
	63	'\" Start of description of a specific option. cmdName gives the
	64	'\" option's name as specified in the class command, dbName gives
65	'\" the option's name in the option database, and dbClass gives
66	'\" the option's class in the option database.
67	'\"
68	'\" .UL arg1 arg2
69	'\" Print arg1 underlined, then print arg2 normally.
70	'\"
71	'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
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74	.if t .wh -1.3i ^B
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79	.ie !"\\$4"" .TP \\$4
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108	.AS Tcl_Interp Tcl_CreateInterp in/out
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177	.el \h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
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207	.de SO
208	.SH "STANDARD OPTIONS"
209	.LP
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212	.ft B
213	..
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217	.ft R
218	.LP
219	See the \\fBoptions\\fR manual entry for details on the standard options.
220	..
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222	.de OP
223	.LP
224	.nf
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226	Command-Line Name: \\fB\\$1\\fR
227	Database Name: \\fB\\$2\\fR
228	Database Class: \\fB\\$3\\fR
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230	.IP
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242	..
243	.de UL
244	\\$1\l'\|0\(ul'\\$2
245	..
246	.TH Tk_CreateSelHandler 3 4.0 Tk "Tk Library Procedures"
247	.BS
248	.SH NAME
249	Tk_CreateSelHandler, Tk_DeleteSelHandler \- arrange to handle requests for a selection
250	.SH SYNOPSIS
251	.nf
252	\fB#include <tk.h>\fR
253	.sp
254	\fBTk_CreateSelHandler\fR(\fItkwin, selection, target, proc, clientData, format\fR)
255	.sp
256	\fBTk_DeleteSelHandler\fR(\fItkwin, selection, target\fR)
257	.SH ARGUMENTS
258	.AS Tk_SelectionProc clientData
259	.AP Tk_Window tkwin in
260	Window for which \fIproc\fR will provide selection information.
261	.AP Atom selection in
262	The name of the selection for which \fIproc\fR will provide
263	selection information.
264	.AP Atom target in
265	Form in which \fIproc\fR can provide the selection (e.g. STRING
266	or FILE_NAME). Corresponds to \fItype\fR arguments in \fBselection\fR
267	commands.
268	.AP Tk_SelectionProc *proc in
269	Procedure to invoke whenever the selection is owned by \fItkwin\fR
270	and the selection contents are requested in the format given by
271	\fItarget\fR.
272	.AP ClientData clientData in
273	Arbitrary one-word value to pass to \fIproc\fR.
274	.AP Atom format in
275	If the selection requestor isn't in this process, \fIformat\fR determines
276	the representation used to transmit the selection to its
277	requestor.
278	.BE
279
280	.SH DESCRIPTION
281	.PP
282	\fBTk_CreateSelHandler\fR arranges for a particular procedure
283	(\fIproc\fR) to be called whenever \fIselection\fR is owned by
284	\fItkwin\fR and the selection contents are requested in the
285	form given by \fItarget\fR.
286	\fITarget\fR should be one of
287	the entries defined in the left column of Table 2 of the
288	X Inter-Client Communication Conventions Manual (ICCCM) or
289	any other form in which an application is willing to present
290	the selection. The most common form is STRING.
291	.PP
292	\fIProc\fR should have arguments and result that match the
293	type \fBTk_SelectionProc\fR:
294	.CS
295	typedef int Tk_SelectionProc(
296	ClientData \fIclientData\fR,
297	int \fIoffset\fR,
298	char *\fIbuffer\fR,
299	int \fImaxBytes\fR);
300	.CE
301	The \fIclientData\fR parameter to \fIproc\fR is a copy of the
302	\fIclientData\fR argument given to \fBTk_CreateSelHandler\fR.
303	Typically, \fIclientData\fR points to a data
304	structure containing application-specific information that is
305	needed to retrieve the selection. \fIOffset\fR specifies an
306	offset position into the selection, \fIbuffer\fR specifies a
307	location at which to copy information about the selection, and
308	\fImaxBytes\fR specifies the amount of space available at
309	\fIbuffer\fR. \fIProc\fR should place a NULL-terminated string
310	at \fIbuffer\fR containing \fImaxBytes\fR or fewer characters
311	(not including the terminating NULL), and it should return a
312	count of the number of non-NULL characters stored at
313	\fIbuffer\fR. If the selection no longer exists (e.g. it once
314	existed but the user deleted the range of characters containing
315	it), then \fIproc\fR should return -1.
316	.PP
317	When transferring large selections, Tk will break them up into
318	smaller pieces (typically a few thousand bytes each) for more
319	efficient transmission. It will do this by calling \fIproc\fR
320	one or more times, using successively higher values of \fIoffset\fR
321	to retrieve successive portions of the selection. If \fIproc\fR
322	returns a count less than \fImaxBytes\fR it means that the entire
323	remainder of the selection has been returned. If \fIproc\fR's return
324	value is \fImaxBytes\fR it means there may be additional information
325	in the selection, so Tk must make another call to \fIproc\fR to
326	retrieve the next portion.
327	.PP
328	\fIProc\fR always returns selection information in the form of a
329	character string. However, the ICCCM allows for information to
330	be transmitted from the selection owner to the selection requestor
331	in any of several formats, such as a string, an array of atoms, an
332	array of integers, etc. The \fIformat\fR argument to
333	\fBTk_CreateSelHandler\fR indicates what format should be used to
334	transmit the selection to its requestor (see the middle column of
335	Table 2 of the ICCCM for examples). If \fIformat\fR is not
336	STRING, then Tk will take the value returned by \fIproc\fR and divided
337	it into fields separated by white space. If \fIformat\fR is ATOM,
338	then Tk will return the selection as an array of atoms, with each
339	field in \fIproc\fR's result treated as the name of one atom. For
340	any other value of \fIformat\fR, Tk will return the selection as an
341	array of 32-bit values where each field of \fIproc\fR's result is
342	treated as a number and translated to a 32-bit value. In any event,
343	the \fIformat\fR atom is returned to the selection requestor along
344	with the contents of the selection.
345	.PP
346	If \fBTk_CreateSelHandler\fR is called when there already exists a
347	handler for \fIselection\fR and \fItarget\fR on \fItkwin\fR, then the
348	existing handler is replaced with a new one.
349	.PP
350	\fBTk_DeleteSelHandler\fR removes the handler given by \fItkwin\fR,
351	\fIselection\fR, and \fItarget\fR, if such a handler exists.
352	If there is no such handler then it has no effect.
353
354	.SH KEYWORDS
355	format, handler, selection, target