ref: a314e313bdd65f8f588cc3188df4b215443c03d7
dir: /lib/c/strcat.c/
#include <string.h>
#undef strcat
char *
strcat(char * restrict dst, const char * restrict src)
{
char *ret = dst;
while (*dst)
++dst;
while (*dst++ = *src++)
;
return ret;
}