diff options
Diffstat (limited to 'doc/StringObj.3')
-rw-r--r-- | doc/StringObj.3 | 544 |
1 files changed, 272 insertions, 272 deletions
diff --git a/doc/StringObj.3 b/doc/StringObj.3 index f326315..78b801e 100644 --- a/doc/StringObj.3 +++ b/doc/StringObj.3 @@ -1,272 +1,272 @@ -'\" -'\" Copyright (c) 1994-1997 Sun Microsystems, Inc. -'\" -'\" See the file "license.terms" for information on usage and redistribution -'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. -'\" -'\" RCS: @(#) $Id: StringObj.3,v 1.20 2005/09/13 21:23:51 dgp Exp $ -'\" -.so man.macros -.TH Tcl_StringObj 3 8.1 Tcl "Tcl Library Procedures" -.BS -.SH NAME -Tcl_NewStringObj, Tcl_NewUnicodeObj, Tcl_SetStringObj, Tcl_SetUnicodeObj, Tcl_GetStringFromObj, Tcl_GetString, Tcl_GetUnicodeFromObj, Tcl_GetUnicode, Tcl_GetUniChar, Tcl_GetCharLength, Tcl_GetRange, Tcl_AppendToObj, Tcl_AppendUnicodeToObj, Tcl_AppendStringsToObj, Tcl_AppendStringsToObjVA, Tcl_AppendObjToObj, Tcl_SetObjLength, Tcl_ConcatObj, Tcl_AttemptSetObjLength \- manipulate Tcl objects as strings -.SH SYNOPSIS -.nf -\fB#include <tcl.h>\fR -.sp -Tcl_Obj * -\fBTcl_NewStringObj\fR(\fIbytes, length\fR) -.sp -Tcl_Obj * -\fBTcl_NewUnicodeObj\fR(\fIunicode, numChars\fR) -.sp -void -\fBTcl_SetStringObj\fR(\fIobjPtr, bytes, length\fR) -.sp -void -\fBTcl_SetUnicodeObj\fR(\fIobjPtr, unicode, numChars\fR) -.sp -char * -\fBTcl_GetStringFromObj\fR(\fIobjPtr, lengthPtr\fR) -.sp -char * -\fBTcl_GetString\fR(\fIobjPtr\fR) -.sp -Tcl_UniChar * -\fBTcl_GetUnicodeFromObj\fR(\fIobjPtr, lengthPtr\fR) -.sp -Tcl_UniChar * -\fBTcl_GetUnicode\fR(\fIobjPtr\fR) -.sp -Tcl_UniChar -\fBTcl_GetUniChar\fR(\fIobjPtr, index\fR) -.sp -int -\fBTcl_GetCharLength\fR(\fIobjPtr\fR) -.sp -Tcl_Obj * -\fBTcl_GetRange\fR(\fIobjPtr, first, last\fR) -.sp -void -\fBTcl_AppendToObj\fR(\fIobjPtr, bytes, length\fR) -.sp -void -\fBTcl_AppendUnicodeToObj\fR(\fIobjPtr, unicode, numChars\fR) -.sp -void -\fBTcl_AppendObjToObj\fR(\fIobjPtr, appendObjPtr\fR) -.sp -void -\fBTcl_AppendStringsToObj\fR(\fIobjPtr, string, string, ... \fB(char *) NULL\fR) -.sp -void -\fBTcl_AppendStringsToObjVA\fR(\fIobjPtr, argList\fR) -.sp -void -\fBTcl_SetObjLength\fR(\fIobjPtr, newLength\fR) -.sp -int -\fBTcl_AttemptSetObjLength\fR(\fIobjPtr, newLength\fR) -.sp -Tcl_Obj * -\fBTcl_ConcatObj\fR(\fIobjc, objv\fR) -.SH ARGUMENTS -.AS "const Tcl_UniChar" *appendObjPtr in/out -.AP "const char" *bytes in -Points to the first byte of an array of UTF-8-encoded bytes -used to set or append to a string object. -This byte array may contain embedded null characters -unless \fInumChars\fR is negative. (Applications needing null bytes -should represent them as the two-byte sequence \fI\\700\\600\fR, use -\fBTcl_ExternalToUtf\fR to convert, or \fBTcl_NewByteArrayObj\fR if -the string is a collection of uninterpreted bytes.) -.AP int length in -The number of bytes to copy from \fIbytes\fR when -initializing, setting, or appending to a string object. -If negative, all bytes up to the first null are used. -.AP "const Tcl_UniChar" *unicode in -Points to the first byte of an array of Unicode characters -used to set or append to a string object. -This byte array may contain embedded null characters -unless \fInumChars\fR is negative. -.AP int numChars in -The number of Unicode characters to copy from \fIunicode\fR when -initializing, setting, or appending to a string object. -If negative, all characters up to the first null character are used. -.AP int index in -The index of the Unicode character to return. -.AP int first in -The index of the first Unicode character in the Unicode range to be -returned as a new object. -.AP int last in -The index of the last Unicode character in the Unicode range to be -returned as a new object. -.AP Tcl_Obj *objPtr in/out -Points to an object to manipulate. -.AP Tcl_Obj *appendObjPtr in -The object to append to \fIobjPtr\fR in \fBTcl_AppendObjToObj\fR. -.AP int *lengthPtr out -If non-NULL, the location where \fBTcl_GetStringFromObj\fR will store -the length of an object's string representation. -.AP "const char" *string in -Null-terminated string value to append to \fIobjPtr\fR. -.AP va_list argList in -An argument list which must have been initialised using -\fBva_start\fR, and cleared using \fBva_end\fR. -.AP int newLength in -New length for the string value of \fIobjPtr\fR, not including the -final null character. -.AP int objc in -The number of elements to concatenate. -.AP Tcl_Obj *objv[] in -The array of objects to concatenate. -.BE - -.SH DESCRIPTION -.PP -The procedures described in this manual entry allow Tcl objects to -be manipulated as string values. They use the internal representation -of the object to store additional information to make the string -manipulations more efficient. In particular, they make a series of -append operations efficient by allocating extra storage space for the -string so that it doesn't have to be copied for each append. -Also, indexing and length computations are optimized because the -Unicode string representation is calculated and cached as needed. -When using the \fBTcl_Append*\fR family of functions where the -interpreter's result is the object being appended to, it is important -to call Tcl_ResetResult first to ensure you are not unintentionally -appending to existing data in the result object. -.PP -\fBTcl_NewStringObj\fR and \fBTcl_SetStringObj\fR create a new object -or modify an existing object to hold a copy of the string given by -\fIbytes\fR and \fIlength\fR. \fBTcl_NewUnicodeObj\fR and -\fBTcl_SetUnicodeObj\fR create a new object or modify an existing -object to hold a copy of the Unicode string given by \fIunicode\fR and -\fInumChars\fR. \fBTcl_NewStringObj\fR and \fBTcl_NewUnicodeObj\fR -return a pointer to a newly created object with reference count zero. -All four procedures set the object to hold a copy of the specified -string. \fBTcl_SetStringObj\fR and \fBTcl_SetUnicodeObj\fR free any -old string representation as well as any old internal representation -of the object. -.PP -\fBTcl_GetStringFromObj\fR and \fBTcl_GetString\fR return an object's -string representation. This is given by the returned byte pointer and -(for \fBTcl_GetStringFromObj\fR) length, which is stored in -\fIlengthPtr\fR if it is non-NULL. If the object's UTF string -representation is invalid (its byte pointer is NULL), the string -representation is regenerated from the object's internal -representation. The storage referenced by the returned byte pointer -is owned by the object manager. It is passed back as a writable -pointer so that extension author creating their own \fBTcl_ObjType\fR -will be able to modify the string representation within the -\fBTcl_UpdateStringProc\fR of their \fBTcl_ObjType\fR. Except for that -limited purpose, the pointer returned by \fBTcl_GetStringFromObj\fR -or \fBTcl_GetString\fR should be treated as read-only. It is -recommended that this pointer be assigned to a (const char *) variable. -Even in the limited situations where writing to this pointer is -acceptable, one should take care to respect the copy-on-write -semantics required by \fBTcl_Obj\fR's, with appropriate calls -to \fBTcl_IsShared\fR and \fBTcl_DuplicateObj\fR prior to any -in-place modification of the string representation. -The procedure \fBTcl_GetString\fR is used in the common case -where the caller does not need the length of the string -representation. -.PP -\fBTcl_GetUnicodeFromObj\fR and \fBTcl_GetUnicode\fR return an object's -value as a Unicode string. This is given by the returned pointer and -(for \fBTcl_GetUnicodeFromObj\fR) length, which is stored in -\fIlengthPtr\fR if it is non-NULL. The storage referenced by the returned -byte pointer is owned by the object manager and should not be modified by -the caller. The procedure \fBTcl_GetUnicode\fR is used in the common case -where the caller does not need the length of the unicode string -representation. -.PP -\fBTcl_GetUniChar\fR returns the \fIindex\fR'th character in the -object's Unicode representation. -.PP -\fBTcl_GetRange\fR returns a newly created object comprised of the -characters between \fIfirst\fR and \fIlast\fR (inclusive) in the -object's Unicode representation. If the object's Unicode -representation is invalid, the Unicode representation is regenerated -from the object's string representation. -.PP -\fBTcl_GetCharLength\fR returns the number of characters (as opposed -to bytes) in the string object. -.PP -\fBTcl_AppendToObj\fR appends the data given by \fIbytes\fR and -\fIlength\fR to the string representation of the object specified by -\fIobjPtr\fR. If the object has an invalid string representation, -then an attempt is made to convert \fIbytes\fR is to the Unicode -format. If the conversion is successful, then the converted form of -\fIbytes\fR is appended to the object's Unicode representation. -Otherwise, the object's Unicode representation is invalidated and -converted to the UTF format, and \fIbytes\fR is appended to the -object's new string representation. -.PP -\fBTcl_AppendUnicodeToObj\fR appends the Unicode string given by -\fIunicode\fR and \fInumChars\fR to the object specified by -\fIobjPtr\fR. If the object has an invalid Unicode representation, -then \fIunicode\fR is converted to the UTF format and appended to the -object's string representation. Appends are optimized to handle -repeated appends relatively efficiently (it overallocates the string -or Unicode space to avoid repeated reallocations and copies of -object's string value). -.PP -\fBTcl_AppendObjToObj\fR is similar to \fBTcl_AppendToObj\fR, but it -appends the string or Unicode value (whichever exists and is best -suited to be appended to \fIobjPtr\fR) of \fIappendObjPtr\fR to -\fIobjPtr\fR. -.PP -\fBTcl_AppendStringsToObj\fR is similar to \fBTcl_AppendToObj\fR -except that it can be passed more than one value to append and -each value must be a null-terminated string (i.e. none of the -values may contain internal null characters). Any number of -\fIstring\fR arguments may be provided, but the last argument -must be a NULL pointer to indicate the end of the list. -.PP -\fBTcl_AppendStringsToObjVA\fR is the same as \fBTcl_AppendStringsToObj\fR -except that instead of taking a variable number of arguments it takes an -argument list. -.PP -The \fBTcl_SetObjLength\fR procedure changes the length of the -string value of its \fIobjPtr\fR argument. If the \fInewLength\fR -argument is greater than the space allocated for the object's -string, then the string space is reallocated and the old value -is copied to the new space; the bytes between the old length of -the string and the new length may have arbitrary values. -If the \fInewLength\fR argument is less than the current length -of the object's string, with \fIobjPtr->length\fR is reduced without -reallocating the string space; the original allocated size for the -string is recorded in the object, so that the string length can be -enlarged in a subsequent call to \fBTcl_SetObjLength\fR without -reallocating storage. In all cases \fBTcl_SetObjLength\fR leaves -a null character at \fIobjPtr->bytes[newLength]\fR. -.PP -\fBTcl_AttemptSetObjLength\fR is identical in function to -\fBTcl_SetObjLength\fR except that if sufficient memory to satisfy the -request cannot be allocated, it does not cause the Tcl interpreter to -\fBpanic\fR. Thus, if \fInewLength\fR is greater than the space -allocated for the object's string, and there is not enough memory -available to satisfy the request, \fBTcl_AttemptSetObjLength\fR will take -no action and return 0 to indicate failure. If there is enough memory -to satisfy the request, \fBTcl_AttemptSetObjLength\fR behaves just like -\fBTcl_SetObjLength\fR and returns 1 to indicate success. -.PP -The \fBTcl_ConcatObj\fR function returns a new string object whose -value is the space-separated concatenation of the string -representations of all of the objects in the \fIobjv\fR -array. \fBTcl_ConcatObj\fR eliminates leading and trailing white space -as it copies the string representations of the \fIobjv\fR array to the -result. If an element of the \fIobjv\fR array consists of nothing but -white space, then that object is ignored entirely. This white-space -removal was added to make the output of the \fBconcat\fR command -cleaner-looking. \fBTcl_ConcatObj\fR returns a pointer to a -newly-created object whose ref count is zero. - -.SH "SEE ALSO" -Tcl_NewObj, Tcl_IncrRefCount, Tcl_DecrRefCount - -.SH KEYWORDS -append, internal representation, object, object type, string object, -string type, string representation, concat, concatenate, unicode +'\"
+'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\"
+'\" RCS: @(#) $Id: StringObj.3,v 1.21 2007/10/28 14:17:39 dkf Exp $
+'\"
+.so man.macros
+.TH Tcl_StringObj 3 8.1 Tcl "Tcl Library Procedures"
+.BS
+.SH NAME
+Tcl_NewStringObj, Tcl_NewUnicodeObj, Tcl_SetStringObj, Tcl_SetUnicodeObj, Tcl_GetStringFromObj, Tcl_GetString, Tcl_GetUnicodeFromObj, Tcl_GetUnicode, Tcl_GetUniChar, Tcl_GetCharLength, Tcl_GetRange, Tcl_AppendToObj, Tcl_AppendUnicodeToObj, Tcl_AppendStringsToObj, Tcl_AppendStringsToObjVA, Tcl_AppendObjToObj, Tcl_SetObjLength, Tcl_ConcatObj, Tcl_AttemptSetObjLength \- manipulate Tcl objects as strings
+.SH SYNOPSIS
+.nf
+\fB#include <tcl.h>\fR
+.sp
+Tcl_Obj *
+\fBTcl_NewStringObj\fR(\fIbytes, length\fR)
+.sp
+Tcl_Obj *
+\fBTcl_NewUnicodeObj\fR(\fIunicode, numChars\fR)
+.sp
+void
+\fBTcl_SetStringObj\fR(\fIobjPtr, bytes, length\fR)
+.sp
+void
+\fBTcl_SetUnicodeObj\fR(\fIobjPtr, unicode, numChars\fR)
+.sp
+char *
+\fBTcl_GetStringFromObj\fR(\fIobjPtr, lengthPtr\fR)
+.sp
+char *
+\fBTcl_GetString\fR(\fIobjPtr\fR)
+.sp
+Tcl_UniChar *
+\fBTcl_GetUnicodeFromObj\fR(\fIobjPtr, lengthPtr\fR)
+.sp
+Tcl_UniChar *
+\fBTcl_GetUnicode\fR(\fIobjPtr\fR)
+.sp
+Tcl_UniChar
+\fBTcl_GetUniChar\fR(\fIobjPtr, index\fR)
+.sp
+int
+\fBTcl_GetCharLength\fR(\fIobjPtr\fR)
+.sp
+Tcl_Obj *
+\fBTcl_GetRange\fR(\fIobjPtr, first, last\fR)
+.sp
+void
+\fBTcl_AppendToObj\fR(\fIobjPtr, bytes, length\fR)
+.sp
+void
+\fBTcl_AppendUnicodeToObj\fR(\fIobjPtr, unicode, numChars\fR)
+.sp
+void
+\fBTcl_AppendObjToObj\fR(\fIobjPtr, appendObjPtr\fR)
+.sp
+void
+\fBTcl_AppendStringsToObj\fR(\fIobjPtr, string, string, ... \fB(char *) NULL\fR)
+.sp
+void
+\fBTcl_AppendStringsToObjVA\fR(\fIobjPtr, argList\fR)
+.sp
+void
+\fBTcl_SetObjLength\fR(\fIobjPtr, newLength\fR)
+.sp
+int
+\fBTcl_AttemptSetObjLength\fR(\fIobjPtr, newLength\fR)
+.sp
+Tcl_Obj *
+\fBTcl_ConcatObj\fR(\fIobjc, objv\fR)
+.SH ARGUMENTS
+.AS "const Tcl_UniChar" *appendObjPtr in/out
+.AP "const char" *bytes in
+Points to the first byte of an array of UTF-8-encoded bytes
+used to set or append to a string object.
+This byte array may contain embedded null characters
+unless \fInumChars\fR is negative. (Applications needing null bytes
+should represent them as the two-byte sequence \fI\e700\e600\fR, use
+\fBTcl_ExternalToUtf\fR to convert, or \fBTcl_NewByteArrayObj\fR if
+the string is a collection of uninterpreted bytes.)
+.AP int length in
+The number of bytes to copy from \fIbytes\fR when
+initializing, setting, or appending to a string object.
+If negative, all bytes up to the first null are used.
+.AP "const Tcl_UniChar" *unicode in
+Points to the first byte of an array of Unicode characters
+used to set or append to a string object.
+This byte array may contain embedded null characters
+unless \fInumChars\fR is negative.
+.AP int numChars in
+The number of Unicode characters to copy from \fIunicode\fR when
+initializing, setting, or appending to a string object.
+If negative, all characters up to the first null character are used.
+.AP int index in
+The index of the Unicode character to return.
+.AP int first in
+The index of the first Unicode character in the Unicode range to be
+returned as a new object.
+.AP int last in
+The index of the last Unicode character in the Unicode range to be
+returned as a new object.
+.AP Tcl_Obj *objPtr in/out
+Points to an object to manipulate.
+.AP Tcl_Obj *appendObjPtr in
+The object to append to \fIobjPtr\fR in \fBTcl_AppendObjToObj\fR.
+.AP int *lengthPtr out
+If non-NULL, the location where \fBTcl_GetStringFromObj\fR will store
+the length of an object's string representation.
+.AP "const char" *string in
+Null-terminated string value to append to \fIobjPtr\fR.
+.AP va_list argList in
+An argument list which must have been initialised using
+\fBva_start\fR, and cleared using \fBva_end\fR.
+.AP int newLength in
+New length for the string value of \fIobjPtr\fR, not including the
+final null character.
+.AP int objc in
+The number of elements to concatenate.
+.AP Tcl_Obj *objv[] in
+The array of objects to concatenate.
+.BE
+
+.SH DESCRIPTION
+.PP
+The procedures described in this manual entry allow Tcl objects to
+be manipulated as string values. They use the internal representation
+of the object to store additional information to make the string
+manipulations more efficient. In particular, they make a series of
+append operations efficient by allocating extra storage space for the
+string so that it does not have to be copied for each append.
+Also, indexing and length computations are optimized because the
+Unicode string representation is calculated and cached as needed.
+When using the \fBTcl_Append*\fR family of functions where the
+interpreter's result is the object being appended to, it is important
+to call Tcl_ResetResult first to ensure you are not unintentionally
+appending to existing data in the result object.
+.PP
+\fBTcl_NewStringObj\fR and \fBTcl_SetStringObj\fR create a new object
+or modify an existing object to hold a copy of the string given by
+\fIbytes\fR and \fIlength\fR. \fBTcl_NewUnicodeObj\fR and
+\fBTcl_SetUnicodeObj\fR create a new object or modify an existing
+object to hold a copy of the Unicode string given by \fIunicode\fR and
+\fInumChars\fR. \fBTcl_NewStringObj\fR and \fBTcl_NewUnicodeObj\fR
+return a pointer to a newly created object with reference count zero.
+All four procedures set the object to hold a copy of the specified
+string. \fBTcl_SetStringObj\fR and \fBTcl_SetUnicodeObj\fR free any
+old string representation as well as any old internal representation
+of the object.
+.PP
+\fBTcl_GetStringFromObj\fR and \fBTcl_GetString\fR return an object's
+string representation. This is given by the returned byte pointer and
+(for \fBTcl_GetStringFromObj\fR) length, which is stored in
+\fIlengthPtr\fR if it is non-NULL. If the object's UTF string
+representation is invalid (its byte pointer is NULL), the string
+representation is regenerated from the object's internal
+representation. The storage referenced by the returned byte pointer
+is owned by the object manager. It is passed back as a writable
+pointer so that extension author creating their own \fBTcl_ObjType\fR
+will be able to modify the string representation within the
+\fBTcl_UpdateStringProc\fR of their \fBTcl_ObjType\fR. Except for that
+limited purpose, the pointer returned by \fBTcl_GetStringFromObj\fR
+or \fBTcl_GetString\fR should be treated as read-only. It is
+recommended that this pointer be assigned to a (const char *) variable.
+Even in the limited situations where writing to this pointer is
+acceptable, one should take care to respect the copy-on-write
+semantics required by \fBTcl_Obj\fR's, with appropriate calls
+to \fBTcl_IsShared\fR and \fBTcl_DuplicateObj\fR prior to any
+in-place modification of the string representation.
+The procedure \fBTcl_GetString\fR is used in the common case
+where the caller does not need the length of the string
+representation.
+.PP
+\fBTcl_GetUnicodeFromObj\fR and \fBTcl_GetUnicode\fR return an object's
+value as a Unicode string. This is given by the returned pointer and
+(for \fBTcl_GetUnicodeFromObj\fR) length, which is stored in
+\fIlengthPtr\fR if it is non-NULL. The storage referenced by the returned
+byte pointer is owned by the object manager and should not be modified by
+the caller. The procedure \fBTcl_GetUnicode\fR is used in the common case
+where the caller does not need the length of the unicode string
+representation.
+.PP
+\fBTcl_GetUniChar\fR returns the \fIindex\fR'th character in the
+object's Unicode representation.
+.PP
+\fBTcl_GetRange\fR returns a newly created object comprised of the
+characters between \fIfirst\fR and \fIlast\fR (inclusive) in the
+object's Unicode representation. If the object's Unicode
+representation is invalid, the Unicode representation is regenerated
+from the object's string representation.
+.PP
+\fBTcl_GetCharLength\fR returns the number of characters (as opposed
+to bytes) in the string object.
+.PP
+\fBTcl_AppendToObj\fR appends the data given by \fIbytes\fR and
+\fIlength\fR to the string representation of the object specified by
+\fIobjPtr\fR. If the object has an invalid string representation,
+then an attempt is made to convert \fIbytes\fR is to the Unicode
+format. If the conversion is successful, then the converted form of
+\fIbytes\fR is appended to the object's Unicode representation.
+Otherwise, the object's Unicode representation is invalidated and
+converted to the UTF format, and \fIbytes\fR is appended to the
+object's new string representation.
+.PP
+\fBTcl_AppendUnicodeToObj\fR appends the Unicode string given by
+\fIunicode\fR and \fInumChars\fR to the object specified by
+\fIobjPtr\fR. If the object has an invalid Unicode representation,
+then \fIunicode\fR is converted to the UTF format and appended to the
+object's string representation. Appends are optimized to handle
+repeated appends relatively efficiently (it overallocates the string
+or Unicode space to avoid repeated reallocations and copies of
+object's string value).
+.PP
+\fBTcl_AppendObjToObj\fR is similar to \fBTcl_AppendToObj\fR, but it
+appends the string or Unicode value (whichever exists and is best
+suited to be appended to \fIobjPtr\fR) of \fIappendObjPtr\fR to
+\fIobjPtr\fR.
+.PP
+\fBTcl_AppendStringsToObj\fR is similar to \fBTcl_AppendToObj\fR
+except that it can be passed more than one value to append and
+each value must be a null-terminated string (i.e. none of the
+values may contain internal null characters). Any number of
+\fIstring\fR arguments may be provided, but the last argument
+must be a NULL pointer to indicate the end of the list.
+.PP
+\fBTcl_AppendStringsToObjVA\fR is the same as \fBTcl_AppendStringsToObj\fR
+except that instead of taking a variable number of arguments it takes an
+argument list.
+.PP
+The \fBTcl_SetObjLength\fR procedure changes the length of the
+string value of its \fIobjPtr\fR argument. If the \fInewLength\fR
+argument is greater than the space allocated for the object's
+string, then the string space is reallocated and the old value
+is copied to the new space; the bytes between the old length of
+the string and the new length may have arbitrary values.
+If the \fInewLength\fR argument is less than the current length
+of the object's string, with \fIobjPtr->length\fR is reduced without
+reallocating the string space; the original allocated size for the
+string is recorded in the object, so that the string length can be
+enlarged in a subsequent call to \fBTcl_SetObjLength\fR without
+reallocating storage. In all cases \fBTcl_SetObjLength\fR leaves
+a null character at \fIobjPtr->bytes[newLength]\fR.
+.PP
+\fBTcl_AttemptSetObjLength\fR is identical in function to
+\fBTcl_SetObjLength\fR except that if sufficient memory to satisfy the
+request cannot be allocated, it does not cause the Tcl interpreter to
+\fBpanic\fR. Thus, if \fInewLength\fR is greater than the space
+allocated for the object's string, and there is not enough memory
+available to satisfy the request, \fBTcl_AttemptSetObjLength\fR will take
+no action and return 0 to indicate failure. If there is enough memory
+to satisfy the request, \fBTcl_AttemptSetObjLength\fR behaves just like
+\fBTcl_SetObjLength\fR and returns 1 to indicate success.
+.PP
+The \fBTcl_ConcatObj\fR function returns a new string object whose
+value is the space-separated concatenation of the string
+representations of all of the objects in the \fIobjv\fR
+array. \fBTcl_ConcatObj\fR eliminates leading and trailing white space
+as it copies the string representations of the \fIobjv\fR array to the
+result. If an element of the \fIobjv\fR array consists of nothing but
+white space, then that object is ignored entirely. This white-space
+removal was added to make the output of the \fBconcat\fR command
+cleaner-looking. \fBTcl_ConcatObj\fR returns a pointer to a
+newly-created object whose ref count is zero.
+
+.SH "SEE ALSO"
+Tcl_NewObj, Tcl_IncrRefCount, Tcl_DecrRefCount
+
+.SH KEYWORDS
+append, internal representation, object, object type, string object,
+string type, string representation, concat, concatenate, unicode
|