ref: 4b9f39b27fb44f607f9b5ba6be2f18b7099b5666 dir: /sys/src/cmd/unix/drawterm/libc/runestrlen.c/
#include <u.h> #include <libc.h> long runestrlen(Rune *s) { return runestrchr(s, 0) - s; }