ref: c38bce1159b6edee799618f49f700ac3616fd2b0
dir: /libc/utfrrune.c/
#include <u.h> #include <libc.h> char* utfrrune(char *s, long c) { long c1; Rune r; char *s1; if(c < Runesync) /* not part of utf sequence */ return strrchr(s, c); s1 = 0; for(;;) { c1 = *(uchar*)s; if(c1 < Runeself) { /* one byte rune */ if(c1 == 0) return s1; if(c1 == c) s1 = s; s++; continue; } c1 = chartorune(&r, s); if(r == c) s1 = s; s += c1; } return 0; }