ref: b9e031951a57b34a700eeb70568d1fd86fc8f01c dir: /sys/src/cmd/unix/drawterm/libc/runestrcat.c/
#include <u.h> #include <libc.h> Rune* runestrcat(Rune *s1, Rune *s2) { runestrcpy(runestrchr(s1, 0), s2); return s1; }