![istream ignore istream ignore](https://img.etb2bimg.com/files/cp/int_1626789029.jpg)
traits::eq_int_type(traits::to_int_type(c), delim) for the next available input character c (in which case c is extracted).end-of-file occurs on the input sequence (in which case the function calls setstate(eofbit), which may throw ios_base::failure (27.5.5.4)).n != numeric_limits::max() (18.3.2) and n characters have been extracted so far.
![istream ignore istream ignore](https://4.bp.blogspot.com/-tvT3XMvEkMc/XFbUOiKkF7I/AAAAAAAAAls/sJTkczwsHt8UfdjZJMiW9cdQFVaPW6OjgCLcBGAs/s1600/cin_teclado.png)
Characters are extracted until any of the following occurs: After constructing a sentry object, extracts characters and discards them. When ignore terminates because it's read the number of characters requested, it always attempts to reads one more character, because it needs to know if condition 2 might also be true (it happened to read the last character so it can take the appropriate action, putting cin in EOF state, or leaving the next character in the buffer for the next read otherwise):Įffects: Behaves as an unformatted input function (as described above). The problem here is the same basic issue as the problem you linked just a different manifestation. ignore is blocking waiting for a third character to be entered (really, checking if it's EOF after those two characters), and by the spec, this is apparently the correct thing to do, I think?
Istream ignore code#
Well, bad news, you're right, the code is blocking at step 2 in ignore.