ref: 3ba1d83d2026ebac616ab17a2126df97c0a7a24c
dir: /sys/src/ape/lib/ap/gen/strncat.c/
#include <string.h> char* strncat(char *s1, const char *s2, size_t n) { char *os1; long nn; os1 = s1; nn = n; while(*s1++) ; s1--; while(*s1++ = *s2++) if(--nn < 0) { s1[-1] = 0; break; } return os1; }