If YES, the receiver releases the memory with free() when it no longer needs the data; if NO it won’t.
An initialized NSString object containing length bytes from bytes interpreted using the encoding encoding. The returned object may be different from the original receiver.
If an error occurs during the creation of the string, then bytes is not freed even if flag is YES. In this case, the caller is responsible for freeing the buffer. This allows the caller to continue trying to create a string with the buffer, without having the buffer deallocated.
Returns an NSString object initialized by using a given format string as a template into which the remaining argument values are substituted according to given locale information. This method is meant to be called from within a variadic function, where the argument list will be available.