Printing Stdout In Command Line App Without Overwriting Pending User Input
- by Chris S
In a basic Unix-shell app, how would you print to stdout without disturbing any pending user input.
e.g. Below is a simple Python app that echos user input. A thread running in the background prints a counter every 1 second.
import threading, time
class MyThread( threading.Thread ):
running = False
def run(self):
self.running = True
i = 0
while self.running:
i += 1
time.sleep(1)
print i
t = MyThread()
t.daemon = True
t.start()
try:
while 1:
inp = raw_input('command> ')
print inp
finally:
t.running = False
Note how the thread mangles the displayed user input as they type it (e.g. hell1o wo2rld3). How would you work around that, so that the shell writes a new line while preserving the line the user's currently typing on?
