ref: a0fd79029b5b1d0a70754a34d0a38c7075b8ae52
dir: /sys/src/libc/port/runestrrchr.c/
#include <u.h>
#include <libc.h>
Rune*
runestrrchr(Rune *s, Rune c)
{
Rune *r;
if(c == 0)
return runestrchr(s, 0);
r = 0;
while(s = runestrchr(s, c))
r = s++;
return r;
}