Don't drop Keypresses outside of readchar_linux() #74
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Calling `tty.setraw` makes it so that subsequent calls to `read()` don't read any of the typed-but-not-read characters. Reading the code, this could be expected since `tty.setraw` is called without explicit parameters, and the [default for when](https://github.com/python/cpython/blob/345572a1a026/Lib/tty.py#L18) is `TCSAFLUSH`, which means: > If optional_actions is TCSAFLUSH, the change shall occur after all output > written to fildes is transmitted, **and all input so far received but not > read shall be discarded before the change is made.** (emphasis mine) Indeed, changing the call to be with `TCSADRAIN` seems to solve the problem of missing keystrokes. However, that solves the problem that any keystrokes that occur outside of `readchar` are dropped fully, but it does not solve the problem that they will be echoed. (They will be echoed because they occur at a point in time that stdin is in "cooked" or "canonical" (non-raw) mode). See magmax#73
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Hello, I am working on similar problem over on https://github.com/Cube707/python-readchar/pull/5 and as my experiences with the unix-termianl are limited, your insigt might be helpfull. If you can find the time you may want to take a look. |
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Calling
tty.setrawmakes it so that subsequent calls toread()don't readany of the typed-but-not-read characters. Reading the code, this could be
expected since
tty.setrawis called without explicit parameters, and thedefault for when
is
TCSAFLUSH, which means:Indeed, changing the call to be with
TCSADRAINseems to solve the problem ofmissing keystrokes.
However, that solves the problem that any keystrokes that occur outside of
readcharare dropped fully, but it does not solve the problem that they willbe echoed. (They will be echoed because they occur at a point in time that
stdin is in "cooked" or "canonical" (non-raw) mode).
See #73