Index of Section 3 Manual Pages
| Interix / SUA | Tcl_UniChar.3 | Interix / SUA |
Utf(3) Tcl Library Procedures Utf(3)
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NAME
Tcl_UniChar, Tcl_UniCharCaseMatch, Tcl_UniCharNcasecmp,
Tcl_UniCharToUtf, Tcl_UtfToUniChar, Tcl_UniCharToUtfD-
String, Tcl_UtfToUniCharDString, Tcl_UniCharLen,
Tcl_UniCharNcmp, Tcl_UtfCharComplete, Tcl_NumUtfChars,
Tcl_UtfFindFirst, Tcl_UtfFindLast, Tcl_UtfNext, Tcl_Utf-
Prev, Tcl_UniCharAtIndex, Tcl_UtfAtIndex, Tcl_UtfBackslash
- routines for manipulating UTF-8 strings.
SYNOPSIS
#include
typedef ... Tcl_UniChar;
int
Tcl_UniCharToUtf(ch, buf)
int
Tcl_UtfToUniChar(src, chPtr)
char * |
Tcl_UniCharToUtfDString(uniStr, numChars, dstPtr) |
Tcl_UniChar * |
Tcl_UtfToUniCharDString(src, len, dstPtr) |
int
Tcl_UniCharLen(uniStr)
int
Tcl_UniCharNcmp(uniStr, uniStr, num)
int |
Tcl_UniCharNcasecmp(uniStr, uniStr, num) |
int |
Tcl_UniCharCaseMatch(uniStr, uniPattern, nocase) |
int
Tcl_UtfNcmp(src, src, num)
int
Tcl_UtfNcasecmp(src, src, num)
int
Tcl_UtfCharComplete(src, len)
int
Tcl_NumUtfChars(src, len)
CONST char * |
Tcl_UtfFindFirst(src, ch) |
CONST char * |
Tcl_UtfFindLast(src, ch) |
CONST char * |
Tcl_UtfNext(src) |
CONST char * |
Tcl_UtfPrev(src, start) |
Tcl_UniChar
Tcl_UniCharAtIndex(src, index)
CONST char * |
Tcl_UtfAtIndex(src, index) |
int
Tcl_UtfBackslash(src, readPtr, dst)
ARGUMENTS
char *buf (out) Buffer in which
the UTF-8 repre-
sentation of the
Tcl_UniChar is
stored. At most
TCL_UTF_MAX bytes
are stored in the
buffer.
int ch (in) The Tcl_UniChar
to be converted
or examined.
Tcl_UniChar *chPtr (out) Filled with the
Tcl_UniChar rep-
resented by the
head of the UTF-8
string.
CONST char *src (in) Pointer to a
UTF-8 string.
CONST Tcl_UniChar *uniStr (in) A null-terminated
Unicode string.
CONST Tcl_UniChar *uniPattern(in) A null-terminated
Unicode string.
int len (in) The length of the
UTF-8 string in
bytes (not UTF-8
characters). If
negative, all
bytes up to the
first null byte
are used.
int numChars (in) The length of the
Unicode string in
characters. Must
be greater than
or equal to 0.
Tcl_DString *dstPtr (in/out) A pointer to a
previously-ini-
tialized
Tcl_DString.
unsigned long num (in) The number of
characters to
compare.
CONST char *start (in) Pointer to the
beginning of a
UTF-8 string.
int index (in) The index of a
character (not
byte) in the
UTF-8 string.
int *readPtr (out) If non-NULL,
filled with the
number of bytes
in the backslash
sequence, includ-
ing the backslash
character.
char *dst (out) Buffer in which
the bytes repre-
sented by the
backslash
sequence are
stored. At most
TCL_UTF_MAX bytes
are stored in the
buffer. |
int nocase (in) ||
Specifies whether |
the match should |
be done case-sen- |
sitive (0) or |
case-insensitive |
(1).
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DESCRIPTION
These routines convert between UTF-8 strings and
Tcl_UniChars. A Tcl_UniChar is a Unicode character repre-
sented as an unsigned, fixed-size quantity. A UTF-8 char-
acter is a Unicode character represented as a varying-
length sequence of up to TCL_UTF_MAX bytes. A multibyte
UTF-8 sequence consists of a lead byte followed by some
number of trail bytes.
TCL_UTF_MAX is the maximum number of bytes that it takes
to represent one Unicode character in the UTF-8 represen-
tation.
Tcl_UniCharToUtf stores the Tcl_UniChar ch as a UTF-8
string in starting at buf. The return value is the number
of bytes stored in buf.
Tcl_UtfToUniChar reads one UTF-8 character starting at src
and stores it as a Tcl_UniChar in *chPtr. The return
value is the number of bytes read from src.. The caller
must ensure that the source buffer is long enough such
that this routine does not run off the end and dereference
non-existent or random memory; if the source buffer is
known to be null-terminated, this will not happen. If the
input is not in proper UTF-8 format, Tcl_UtfToUniChar will
store the first byte of src in *chPtr as a Tcl_UniChar
between 0x0000 and 0x00ff and return 1.
Tcl_UniCharToUtfDString converts the given Unicode string
to UTF-8, storing the result in a previously-initialized
Tcl_DString. You must specify the length of the given
Unicode string. The return value is a pointer to the
UTF-8 representation of the Unicode string. Storage for
the return value is appended to the end of the
Tcl_DString.
Tcl_UtfToUniCharDString converts the given UTF-8 string to
Unicode, storing the result in the previously-initialized
Tcl_DString. you may either specify the length of the
given UTF-8 string or "-1", in which case
Tcl_UtfToUniCharDString uses strlen to calculate the
length. The return value is a pointer to the Unicode rep-
resentation of the UTF-8 string. Storage for the return
value is appended to the end of the Tcl_DString. The Uni-
code string is terminated with a Unicode null character.
Tcl_UniCharLen corresponds to strlen for Unicode charac-
ters. It accepts a null-terminated Unicode string and
returns the number of Unicode characters (not bytes) in
that string.
Tcl_UniCharNcmp and Tcl_UniCharNcasecmp correspond to
strncmp and strncasecmp, respectively, for Unicode charac-
ters. They accepts two null-terminated Unicode strings
and the number of characters to compare. Both strings are
assumed to be at least len characters long.
Tcl_UniCharNcmp compares the two strings character-by-
character according to the Unicode character ordering. It
returns an integer greater than, equal to, or less than 0
if the first string is greater than, equal to, or less
than the second string respectively. Tcl_UniCharNcasecmp
is the Unicode case insensitive version.
Tcl_UniCharCaseMatch is the Unicode equivalent to |
Tcl_StringCaseMatch. It accepts a null-terminated Unicode |
string, a Unicode pattern, and a boolean value specifying |
whether the match should be case sensitive and returns |
whether the string matches the pattern.
Tcl_UtfNcmp corresponds to strncmp for UTF-8 strings. It
accepts two null-terminated UTF-8 strings and the number
of characters to compare. (Both strings are assumed to be
at least len characters long.) Tcl_UtfNcmp compares the
two strings character-by-character according to the Uni-
code character ordering. It returns an integer greater
than, equal to, or less than 0 if the first string is
greater than, equal to, or less than the second string
respectively.
Tcl_UtfNcasecmp corresponds to strncasecmp for UTF-8
strings. It is similar to Tcl_UtfNcmp except comparisons
ignore differences in case when comparing upper, lower or
title case characters.
Tcl_UtfCharComplete returns 1 if the source UTF-8 string
src of length len bytes is long enough to be decoded by
Tcl_UtfToUniChar, or 0 otherwise. This function does not
guarantee that the UTF-8 string is properly formed. This
routine is used by procedures that are operating on a byte
at a time and need to know if a full Tcl_UniChar has been
seen.
Tcl_NumUtfChars corresponds to strlen for UTF-8 strings.
It returns the number of Tcl_UniChars that are represented
by the UTF-8 string src. The length of the source string
is len bytes. If the length is negative, all bytes up to
the first null byte are used.
Tcl_UtfFindFirst corresponds to strchr for UTF-8 strings.
It returns a pointer to the first occurrence of the
Tcl_UniChar ch in the null-terminated UTF-8 string src.
The null terminator is considered part of the UTF-8
string.
Tcl_UtfFindLast corresponds to strrchr for UTF-8 strings.
It returns a pointer to the last occurrence of the
Tcl_UniChar ch in the null-terminated UTF-8 string src.
The null terminator is considered part of the UTF-8
string.
Given src, a pointer to some location in a UTF-8 string,
Tcl_UtfNext returns a pointer to the next UTF-8 character
in the string. The caller must not ask for the next char-
acter after the last character in the string if the string
is not terminated by a null character.
Given src, a pointer to some location in a UTF-8 string
(or to a null byte immediately following such a string),
Tcl_UtfPrev returns a pointer to the closest preceding
byte that starts a UTF-8 character. This function will
not back up to a position before start, the start of the
UTF-8 string. If src was already at start, the return
value will be start.
Tcl_UniCharAtIndex corresponds to a C string array deref-
erence or the Pascal Ord() function. It returns the
Tcl_UniChar represented at the specified character (not
byte) index in the UTF-8 string src. The source string
must contain at least index characters. Behavior is unde-
fined if a negative index is given.
Tcl_UtfAtIndex returns a pointer to the specified charac-
ter (not byte) index in the UTF-8 string src. The source
string must contain at least index characters. This is
equivalent to calling Tcl_UtfNext index times. If a nega-
tive index is given, the return pointer points to the
first character in the source string.
Tcl_UtfBackslash is a utility procedure used by several of
the Tcl commands. It parses a backslash sequence and
stores the properly formed UTF-8 character represented by
the backslash sequence in the output buffer dst. At most
TCL_UTF_MAX bytes are stored in the buffer. Tcl_UtfBack-
slash modifies *readPtr to contain the number of bytes in
the backslash sequence, including the backslash character.
The return value is the number of bytes stored in the out-
put buffer.
See the Tcl manual entry for information on the valid
backslash sequences. All of the sequences described in
the Tcl manual entry are supported by Tcl_UtfBackslash.
KEYWORDS
utf, unicode, backslash
Tcl 8.1 Utf(3)