Tcl_UtfToUpper(3tcl) Tcl Library Procedures Tcl_UtfToUpper(3tcl)
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NAME
Tcl_UniCharToUpper, Tcl_UniCharToLower, Tcl_UniCharToTitle,
Tcl_UtfToUpper, Tcl_UtfToLower, Tcl_UtfToTitle - routines for manipu-
lating the case of Unicode characters and UTF-8 strings
SYNOPSIS
#include <tcl.h>
Tcl_UniChar
Tcl_UniCharToUpper(ch)
Tcl_UniChar
Tcl_UniCharToLower(ch)
Tcl_UniChar
Tcl_UniCharToTitle(ch)
int
Tcl_UtfToUpper(str)
int
Tcl_UtfToLower(str)
int
Tcl_UtfToTitle(str)
ARGUMENTS
int ch (in) The Unicode character to be converted.
char *str (in/out) Pointer to UTF-8 string to be converted in
place.
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DESCRIPTION
The first three routines convert the case of individual Unicode charac-
ters:
If ch represents a lower-case character, Tcl_UniCharToUpper returns the
corresponding upper-case character. If no upper-case character is de-
fined, it returns the character unchanged.
If ch represents an upper-case character, Tcl_UniCharToLower returns
the corresponding lower-case character. If no lower-case character is
defined, it returns the character unchanged.
If ch represents a lower-case character, Tcl_UniCharToTitle returns the
corresponding title-case character. If no title-case character is de-
fined, it returns the corresponding upper-case character. If no upper-
case character is defined, it returns the character unchanged. Title-
case is defined for a small number of characters that have a different
appearance when they are at the beginning of a capitalized word.
The next three routines convert the case of UTF-8 strings in place in
memory:
Tcl_UtfToUpper changes every UTF-8 character in str to upper-case. Be-
cause changing the case of a character may change its size, the byte
offset of each character in the resulting string may differ from its
original location. Tcl_UtfToUpper writes a null byte at the end of the
converted string. Tcl_UtfToUpper returns the new length of the string
in bytes. This new length is guaranteed to be no longer than the orig-
inal string length.
Tcl_UtfToLower is the same as Tcl_UtfToUpper except it turns each char-
acter in the string into its lower-case equivalent.
Tcl_UtfToTitle is the same as Tcl_UtfToUpper except it turns the first
character in the string into its title-case equivalent and all follow-
ing characters into their lower-case equivalents.
BUGS
At this time, the case conversions are only defined for the Unicode
plane 0 characters. The result for Unicode characters above 0xFFFF is
undefined, but - actually - only the lower 16 bits of the character
value is handled.
KEYWORDS
utf, unicode, toupper, tolower, totitle, case
Tcl 8.1 Tcl_UtfToUpper(3tcl)
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