ref: 1145d79a11e8bf6852d8ee786bcad1f2a9ab2ad7
dir: /sys/src/libc/port/runestrchr.c/
#include <u.h>
#include <libc.h>
Rune*
runestrchr(Rune *s, Rune c)
{
Rune r;
if(c == 0)
while(*s++)
;
else
while((r = *s++) != c)
if(r == 0)
return 0;
return s-1;
}