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pythonncursestmuxcurses

How to prevent glitches appear in curses app?

I'm developing app with curses in Python. And few seconds after app starts some glitches appear randomly. Normal With glitches

First I thought it's because of tmux and $TERM variable, but it is set to screen-256. Running app outside tmux also causes this kind of glitch.

Here is the code that initializes curses screen

Solution

  • The example does this:

    import curses
from threading import Thread


class Screen(object):
    def __init__(self):
        self.maxx = None
        self.maxy = None

self.run()

    implying that your application could have multiple threads writing to the screen. But curses is normally not thread-safe, so you'll end up with the threads using theirs - and other threads - values of global or static variables. It won't work well.

    If you want to use curses in a multi-threaded application, you'll have to either ensure that only one thread uses curses, or (probably) compile your own copy of the ncurses library which has rudimentary support for re-entrant code, and work within the constraints of that configuration.

    Further reading: