ref: 0d2a10e4416dc7e9d94c8f37e4b0b27ddf2ccc73 dir: /sys/src/ape/lib/ap/gen/strcat.c/
#include <string.h> char* strcat(char *s1, const char *s2) { strcpy(strchr(s1, 0), s2); return s1; }