RUNE(2) RUNE(2)
NAME
runetochar, chartorune, runelen, fullrune, utflen, utfrune,
utfrrune, utfutf - rune/UTF conversion
SYNOPSIS
int runetochar(char *s, Rune *r)
int chartorune(Rune *r, char *s)
int runelen(long r)
int fullrune(char *s, int n)
int utflen(char *s)
char* utfrune(char *s, long c)
char* utfrrune(char *s, long c)
char* utfutf(char *s1, char *s2)
DESCRIPTION
These routines convert to and from a UTF byte stream and
runes.
Runetochar copies one rune at r to at most UTFmax characters
starting at s and returns the number of characters copied.
UTFmax, defined as 3 in <libc.h>, is the maximum number of
bytes required to represent a rune.
Chartorune copies at most UTFmax characters starting at s to
one rune at r and returns the number of characters copied.
If the characters are not exactly in UTF format, chartorune
will convert to 0x80 and return 1.
Runelen returns the number of characters required to convert
r into UTF.
Fullrune returns 1 if the string s of length n is long
enough to be decoded by chartorune and 0 otherwise. This
does not guarantee that the string contains a legal UTF
encoding. This routine is used by programs that obtain
input a character at a time and need to know when a full
rune has arrived.
The following routines are analogous to the corresponding
string routines with utf substituted for str and rune sub-
stituted for chr.
Utflen returns the number of runes that are represented by
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RUNE(2) RUNE(2)
the UTF string s.
Utfrune (utfrrune) returns a pointer to the first (last)
occurrence of rune c in the UTF string s, or 0 if c does not
occur in the string. The NUL character terminating a string
is considered to be part of the string s.
Utfutf returns a pointer to the first occurrence of the UTF
string s2 as a UTF substring of s1, or 0 if there is none.
If s2 is the null string, utfutf returns s1.
SEE ALSO
utf(6), tcs(1),
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