#include <string.h>
char *strcpy(char *s1, const char *s2);
strcpy copies the string pointed to by s2 (including the terminating null character) into the array pointed to by s1. The behaviour of strcpy is undefined if copying takes place between objects that overlap.
strcpy returns the value of s1.
strcpy conforms to ISO/IEC 9899:1990 (C90) and ISO/IEC 9899:1999 (C99).