ref: 5ac3a0d4c1a9d7e4d3912c4770084b885007aca6
dir: /src/libc/string/strcat.c/
#include <string.h> #undef strcat char * strcat(char *restrict s1, const char *restrict s2) { char *ret = s1; while (*s1) ++s1; while ((*s1++ = *s2++) != 0) ; return ret; }