[OpenSPARC-T2-SAM] / sam-t2 / devtools / v9 / man / man3 / Tcl_DStringResult.3

'\"
'\" Copyright (c) 1993 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
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'\" 
'\" RCS: @(#) $Id: DString.3,v 1.9 2002/02/08 02:52:54 dgp Exp $
'\" 
'\" The definitions below are for supplemental macros used in Tcl/Tk
'\" manual entries.
'\"
'\" .AP type name in/out ?indent?
'\"	Start paragraph describing an argument to a library procedure.
'\"	type is type of argument (int, etc.), in/out is either "in", "out",
'\"	or "in/out" to describe whether procedure reads or modifies arg,
'\"	and indent is equivalent to second arg of .IP (shouldn't ever be
'\"	needed;  use .AS below instead)
'\"
'\" .AS ?type? ?name?
'\"	Give maximum sizes of arguments for setting tab stops.  Type and
'\"	name are examples of largest possible arguments that will be passed
'\"	to .AP later.  If args are omitted, default tab stops are used.
'\"
'\" .BS
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'\"	options follow on successive lines, in four columns separated
'\"	by tabs.
'\"
'\" .SE
'\"	End of list of standard options for a Tk widget.
'\"
'\" .OP cmdName dbName dbClass
'\"	Start of description of a specific option.  cmdName gives the
'\"	option's name as specified in the class command, dbName gives
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'\"
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.if t .wh -1.3i ^B
.nr ^l \n(.l
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.de AP
.ie !"\\$4"" .TP \\$4
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.   ie !"\\$2"" .TP \\n()Cu
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.\}
.ta \\n()Au \\n()Bu
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\&\\$1	\\fI\\$2\\fP	(\\$3)
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.AS Tcl_Interp Tcl_CreateInterp in/out
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.\}
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.LP
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.TH Tcl_DString 3 7.4 Tcl "Tcl Library Procedures"
.BS
.SH NAME
Tcl_DStringInit, Tcl_DStringAppend, Tcl_DStringAppendElement, Tcl_DStringStartSublist, Tcl_DStringEndSublist, Tcl_DStringLength, Tcl_DStringValue, Tcl_DStringSetLength, Tcl_DStringTrunc, Tcl_DStringFree, Tcl_DStringResult, Tcl_DStringGetResult \- manipulate dynamic strings
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
\fBTcl_DStringInit\fR(\fIdsPtr\fR)
.sp
char *
\fBTcl_DStringAppend\fR(\fIdsPtr, string, length\fR)
.sp
char *
\fBTcl_DStringAppendElement\fR(\fIdsPtr, string\fR)
.sp
\fBTcl_DStringStartSublist\fR(\fIdsPtr\fR)
.sp
\fBTcl_DStringEndSublist\fR(\fIdsPtr\fR)
.sp
int
\fBTcl_DStringLength\fR(\fIdsPtr\fR)
.sp
char *
\fBTcl_DStringValue\fR(\fIdsPtr\fR)
.sp
\fBTcl_DStringSetLength\fR(\fIdsPtr, newLength\fR)
.sp
\fBTcl_DStringTrunc\fR(\fIdsPtr, newLength\fR)
.sp
\fBTcl_DStringFree\fR(\fIdsPtr\fR)
.sp
\fBTcl_DStringResult\fR(\fIinterp, dsPtr\fR)
.sp
\fBTcl_DStringGetResult\fR(\fIinterp, dsPtr\fR)
.SH ARGUMENTS
.AS Tcl_DString newLength
.AP Tcl_DString *dsPtr in/out
Pointer to structure that is used to manage a dynamic string.
.AP "CONST char" *string in
Pointer to characters to add to dynamic string.
.AP int length in
Number of characters from string to add to dynamic string.  If -1,
add all characters up to null terminating character.
.AP int newLength in
New length for dynamic string, not including null terminating
character.
.AP Tcl_Interp *interp in/out
Interpreter whose result is to be set from or moved to the
dynamic string.
.BE

.SH DESCRIPTION
.PP
Dynamic strings provide a mechanism for building up arbitrarily long
strings by gradually appending information.  If the dynamic string is
short then there will be no memory allocation overhead;  as the string
gets larger, additional space will be allocated as needed.
.PP
\fBTcl_DStringInit\fR initializes a dynamic string to zero length.
The Tcl_DString structure must have been allocated by the caller.
No assumptions are made about the current state of the structure;
anything already in it is discarded.
If the structure has been used previously, \fBTcl_DStringFree\fR should
be called first to free up any memory allocated for the old
string.
.PP
\fBTcl_DStringAppend\fR adds new information to a dynamic string,
allocating more memory for the string if needed.
If \fIlength\fR is less than zero then everything in \fIstring\fR
is appended to the dynamic string;  otherwise \fIlength\fR
specifies the number of bytes to append.
\fBTcl_DStringAppend\fR returns a pointer to the characters of
the new string.  The string can also be retrieved from the
\fIstring\fR field of the Tcl_DString structure.
.PP
\fBTcl_DStringAppendElement\fR is similar to \fBTcl_DStringAppend\fR
except that it doesn't take a \fIlength\fR argument (it appends
all of \fIstring\fR) and it converts the string to a proper list element
before appending.
\fBTcl_DStringAppendElement\fR adds a separator space before the
new list element unless the new list element is the first in a
list or sub-list (i.e. either the current string is empty, or it
contains the single character ``{'', or the last two characters of
the current string are `` {'').
\fBTcl_DStringAppendElement\fR returns a pointer to the
characters of the new string.
.PP
\fBTcl_DStringStartSublist\fR and \fBTcl_DStringEndSublist\fR can be
used to create nested lists.
To append a list element that is itself a sublist, first
call \fBTcl_DStringStartSublist\fR, then call \fBTcl_DStringAppendElement\fR
for each of the elements in the sublist, then call
\fBTcl_DStringEndSublist\fR to end the sublist.
\fBTcl_DStringStartSublist\fR appends a space character if needed,
followed by an open brace;  \fBTcl_DStringEndSublist\fR appends
a close brace.
Lists can be nested to any depth.
.PP
\fBTcl_DStringLength\fR is a macro that returns the current length
of a dynamic string (not including the terminating null character).
\fBTcl_DStringValue\fR is a  macro that returns a pointer to the
current contents of a dynamic string.
.PP
.PP
\fBTcl_DStringSetLength\fR changes the length of a dynamic string.
If \fInewLength\fR is less than the string's current length, then
the string is truncated.
If \fInewLength\fR is greater than the string's current length,
then the string will become longer and new space will be allocated
for the string if needed.
However, \fBTcl_DStringSetLength\fR will not initialize the new
space except to provide a terminating null character;  it is up to the
caller to fill in the new space.
\fBTcl_DStringSetLength\fR does not free up the string's storage space
even if the string is truncated to zero length, so \fBTcl_DStringFree\fR
will still need to be called.
.PP
\fBTcl_DStringTrunc\fR changes the length of a dynamic string.
This procedure is now deprecated.  \fBTcl_DStringSetLength\fR  should
be used instead.
.PP
\fBTcl_DStringFree\fR should be called when you're finished using
the string.  It frees up any memory that was allocated for the string
and reinitializes the string's value to an empty string.
.PP
\fBTcl_DStringResult\fR sets the result of \fIinterp\fR to the value of
the dynamic string given by \fIdsPtr\fR.  It does this by moving
a pointer from \fIdsPtr\fR to the interpreter's result.
This saves the cost of allocating new memory and copying the string.
\fBTcl_DStringResult\fR also reinitializes the dynamic string to
an empty string.
.PP
\fBTcl_DStringGetResult\fR does the opposite of \fBTcl_DStringResult\fR.
It sets the value of \fIdsPtr\fR to the result of \fIinterp\fR and
it clears \fIinterp\fR's result.
If possible it does this by moving a pointer rather than by copying
the string.

.SH KEYWORDS
append, dynamic string, free, result
Commit	Line	Data
920dae64 AT	1	'\"
	2	'\" Copyright (c) 1993 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: DString.3,v 1.9 2002/02/08 02:52:54 dgp 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	'\"
	29	'\" .BE
	30	'\" End of box enclosure.
	31	'\"
	32	'\" .CS
	33	'\" Begin code excerpt.
	34	'\"
	35	'\" .CE
	36	'\" End code excerpt.
	37	'\"
	38	'\" .VS ?version? ?br?
	39	'\" Begin vertical sidebar, for use in marking newly-changed parts
	40	'\" of man pages. The first argument is ignored and used for recording
	41	'\" the version when the .VS was added, so that the sidebars can be
	42	'\" found and removed when they reach a certain age. If another argument
	43	'\" is present, then a line break is forced before starting the sidebar.
	44	'\"
	45	'\" .VE
	46	'\" End of vertical sidebar.
	47	'\"
	48	'\" .DS
	49	'\" Begin an indented unfilled display.
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	52	'\" End of indented unfilled display.
	53	'\"
	54	'\" .SO
	55	'\" Start of list of standard options for a Tk widget. The
	56	'\" options follow on successive lines, in four columns separated
	57	'\" by tabs.
	58	'\"
	59	'\" .SE
	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 $
72	'\"
73	'\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
74	.if t .wh -1.3i ^B
75	.nr ^l \n(.l
76	.ad b
77	'\" # Start an argument description
78	.de AP
79	.ie !"\\$4"" .TP \\$4
80	.el \{\
81	. ie !"\\$2"" .TP \\n()Cu
82	. el .TP 15
83	.\}
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107	..
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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202	.fi
203	.RE
204	.sp
205	..
206	'\" # SO - start of list of standard options
207	.de SO
208	.SH "STANDARD OPTIONS"
209	.LP
210	.nf
211	.ta 5.5c 11c
212	.ft B
213	..
214	'\" # SE - end of list of standard options
215	.de SE
216	.fi
217	.ft R
218	.LP
219	See the \\fBoptions\\fR manual entry for details on the standard options.
220	..
221	'\" # OP - start of full description for a single option
222	.de OP
223	.LP
224	.nf
225	.ta 4c
226	Command-Line Name: \\fB\\$1\\fR
227	Database Name: \\fB\\$2\\fR
228	Database Class: \\fB\\$3\\fR
229	.fi
230	.IP
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239	.de CE
240	.fi
241	.RE
242	..
243	.de UL
244	\\$1\l'\|0\(ul'\\$2
245	..
246	.TH Tcl_DString 3 7.4 Tcl "Tcl Library Procedures"
247	.BS
248	.SH NAME
249	Tcl_DStringInit, Tcl_DStringAppend, Tcl_DStringAppendElement, Tcl_DStringStartSublist, Tcl_DStringEndSublist, Tcl_DStringLength, Tcl_DStringValue, Tcl_DStringSetLength, Tcl_DStringTrunc, Tcl_DStringFree, Tcl_DStringResult, Tcl_DStringGetResult \- manipulate dynamic strings
250	.SH SYNOPSIS
251	.nf
252	\fB#include <tcl.h>\fR
253	.sp
254	\fBTcl_DStringInit\fR(\fIdsPtr\fR)
255	.sp
256	char *
257	\fBTcl_DStringAppend\fR(\fIdsPtr, string, length\fR)
258	.sp
259	char *
260	\fBTcl_DStringAppendElement\fR(\fIdsPtr, string\fR)
261	.sp
262	\fBTcl_DStringStartSublist\fR(\fIdsPtr\fR)
263	.sp
264	\fBTcl_DStringEndSublist\fR(\fIdsPtr\fR)
265	.sp
266	int
267	\fBTcl_DStringLength\fR(\fIdsPtr\fR)
268	.sp
269	char *
270	\fBTcl_DStringValue\fR(\fIdsPtr\fR)
271	.sp
272	\fBTcl_DStringSetLength\fR(\fIdsPtr, newLength\fR)
273	.sp
274	\fBTcl_DStringTrunc\fR(\fIdsPtr, newLength\fR)
275	.sp
276	\fBTcl_DStringFree\fR(\fIdsPtr\fR)
277	.sp
278	\fBTcl_DStringResult\fR(\fIinterp, dsPtr\fR)
279	.sp
280	\fBTcl_DStringGetResult\fR(\fIinterp, dsPtr\fR)
281	.SH ARGUMENTS
282	.AS Tcl_DString newLength
283	.AP Tcl_DString *dsPtr in/out
284	Pointer to structure that is used to manage a dynamic string.
285	.AP "CONST char" *string in
286	Pointer to characters to add to dynamic string.
287	.AP int length in
288	Number of characters from string to add to dynamic string. If -1,
289	add all characters up to null terminating character.
290	.AP int newLength in
291	New length for dynamic string, not including null terminating
292	character.
293	.AP Tcl_Interp *interp in/out
294	Interpreter whose result is to be set from or moved to the
295	dynamic string.
296	.BE
297
298	.SH DESCRIPTION
299	.PP
300	Dynamic strings provide a mechanism for building up arbitrarily long
301	strings by gradually appending information. If the dynamic string is
302	short then there will be no memory allocation overhead; as the string
303	gets larger, additional space will be allocated as needed.
304	.PP
305	\fBTcl_DStringInit\fR initializes a dynamic string to zero length.
306	The Tcl_DString structure must have been allocated by the caller.
307	No assumptions are made about the current state of the structure;
308	anything already in it is discarded.
309	If the structure has been used previously, \fBTcl_DStringFree\fR should
310	be called first to free up any memory allocated for the old
311	string.
312	.PP
313	\fBTcl_DStringAppend\fR adds new information to a dynamic string,
314	allocating more memory for the string if needed.
315	If \fIlength\fR is less than zero then everything in \fIstring\fR
316	is appended to the dynamic string; otherwise \fIlength\fR
317	specifies the number of bytes to append.
318	\fBTcl_DStringAppend\fR returns a pointer to the characters of
319	the new string. The string can also be retrieved from the
320	\fIstring\fR field of the Tcl_DString structure.
321	.PP
322	\fBTcl_DStringAppendElement\fR is similar to \fBTcl_DStringAppend\fR
323	except that it doesn't take a \fIlength\fR argument (it appends
324	all of \fIstring\fR) and it converts the string to a proper list element
325	before appending.
326	\fBTcl_DStringAppendElement\fR adds a separator space before the
327	new list element unless the new list element is the first in a
328	list or sub-list (i.e. either the current string is empty, or it
329	contains the single character ``{'', or the last two characters of
330	the current string are `` {'').
331	\fBTcl_DStringAppendElement\fR returns a pointer to the
332	characters of the new string.
333	.PP
334	\fBTcl_DStringStartSublist\fR and \fBTcl_DStringEndSublist\fR can be
335	used to create nested lists.
336	To append a list element that is itself a sublist, first
337	call \fBTcl_DStringStartSublist\fR, then call \fBTcl_DStringAppendElement\fR
338	for each of the elements in the sublist, then call
339	\fBTcl_DStringEndSublist\fR to end the sublist.
340	\fBTcl_DStringStartSublist\fR appends a space character if needed,
341	followed by an open brace; \fBTcl_DStringEndSublist\fR appends
342	a close brace.
343	Lists can be nested to any depth.
344	.PP
345	\fBTcl_DStringLength\fR is a macro that returns the current length
346	of a dynamic string (not including the terminating null character).
347	\fBTcl_DStringValue\fR is a macro that returns a pointer to the
348	current contents of a dynamic string.
349	.PP
350	.PP
351	\fBTcl_DStringSetLength\fR changes the length of a dynamic string.
352	If \fInewLength\fR is less than the string's current length, then
353	the string is truncated.
354	If \fInewLength\fR is greater than the string's current length,
355	then the string will become longer and new space will be allocated
356	for the string if needed.
357	However, \fBTcl_DStringSetLength\fR will not initialize the new
358	space except to provide a terminating null character; it is up to the
359	caller to fill in the new space.
360	\fBTcl_DStringSetLength\fR does not free up the string's storage space
361	even if the string is truncated to zero length, so \fBTcl_DStringFree\fR
362	will still need to be called.
363	.PP
364	\fBTcl_DStringTrunc\fR changes the length of a dynamic string.
365	This procedure is now deprecated. \fBTcl_DStringSetLength\fR should
366	be used instead.
367	.PP
368	\fBTcl_DStringFree\fR should be called when you're finished using
369	the string. It frees up any memory that was allocated for the string
370	and reinitializes the string's value to an empty string.
371	.PP
372	\fBTcl_DStringResult\fR sets the result of \fIinterp\fR to the value of
373	the dynamic string given by \fIdsPtr\fR. It does this by moving
374	a pointer from \fIdsPtr\fR to the interpreter's result.
375	This saves the cost of allocating new memory and copying the string.
376	\fBTcl_DStringResult\fR also reinitializes the dynamic string to
377	an empty string.
378	.PP
379	\fBTcl_DStringGetResult\fR does the opposite of \fBTcl_DStringResult\fR.
380	It sets the value of \fIdsPtr\fR to the result of \fIinterp\fR and
381	it clears \fIinterp\fR's result.
382	If possible it does this by moving a pointer rather than by copying
383	the string.
384
385	.SH KEYWORDS
386	append, dynamic string, free, result