ref: fe3430ea998a3a494fa22ed574f97834cff38f7f
dir: /sys/src/libc/port/runestrncat.c/
#include <u.h> #include <libc.h> Rune* runestrncat(Rune *s1, Rune *s2, long n) { Rune *os1; os1 = s1; s1 = runestrchr(s1, 0); while(*s1++ = *s2++) if(--n < 0) { s1[-1] = 0; break; } return os1; }