cpp/io/basic istream/read

Extracts characters from stream.

Behaves as. After constructing and checking the sentry object, extracts characters and stores them into successive locations of the character array whose first element is pointed to by. Characters are extracted and stored until any of the following conditions occurs:


 * characters were extracted and stored


 * end of file condition occurs on the input sequence (in which case, is called). The number of successfully extracted characters can be queried using.