char *strncat(char * dest , const char * src , size_t n );
DESCRIPTION
The strcat() function appends the src string to the dest string overwriting the `\0' character at the end of dest, and then adds a terminating `\0' character. The
strings may not overlap, and the dest string must have
enough space for the result.
The strncat() function is similar, except that only the first n characters of src are appended to dest.
RETURN VALUE
The strcat() and strncat() functions return a pointer
to the resulting string dest.