Tags: #python #python3 #ansi #escape #progress
# https://mdk.fr/blog/how-apt-does-its-fancy-progress-bar.html
#
# For the record here's what's used (\033 is ESC):
#
# `ESC 7` is DECSC (Save Cursor)
# `ESC 8` is DECRC (Restore Cursor)
# `ESC [ Pn ; Pn r` is DECSTBM (Set Top and Bottom Margins)
# `ESC [ Pn A` is CUU (Cursor Up)
# `ESC [ Pn ; Pn f` is HVP (Horizontal and Vertical Position)
# `ESC [ Ps K` is EL (Erase In Line)
import os
import time
from datetime import datetime
columns, lines = os.get_terminal_size()
def write(s):
print(s, end="")
time.sleep(1)
write("\n") # Ensure the last line is available.
write("\0337") # Save cursor position
write(f"\033[0;{lines-1}r") # Reserve the bottom line
write("\0338") # Restore the cursor position
write("\033[1A") # Move up one line
try:
for i in range(250):
time.sleep(0.2)
write(f"Hello {i}")
write("\0337") # Save cursor position
write(f"\033[{lines};0f") # Move cursor to the bottom margin
write(datetime.now().isoformat()) # Write the date
write("\0338") # Restore cursor position
write("\n")
except KeyboardInterrupt:
pass
finally:
write("\0337") # Save cursor position
write(f"\033[0;{lines}r") # Drop margin reservation
write(f"\033[{lines};0f") # Move the cursor to the bottom line
write("\033[0K") # Clean that line
write("\0338") # Restore cursor position