How can I flush unread data from a tty input queue on a UNIX system?
buffer, c, unix
Solution
When your program wants to start reading characters, it must drain the buffer of existing characters and then wait to read the character.
Otherwise, it will read the last character entered, not the last character entered after right now.
Naturally, you do not need to do anything with the read characters; but, you do need to read them.
Problem
My program has to read just ONE character from the standard input, and so I use `read(0, buffer, 1)`. But if the user insert more than one single character, they remain in some buffer and when I call a `read` again they are still there. So, how can I discard these characters? I want that when I call a `read` again, the buffer is filled with the new character, not with the old ones. An example: I've a `read(0, buffer, 1)` and the user writes abcde. My buffer contains a (and it's right), but then I call `read(0, buffer, 1)` again and I want the next character written by the user from now, and not the b written before.