ref: dc952dad295700a836cf91ec66b1c443e5bbb4b7
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;
}