zeroterm.py

"""
zeroterm is a light weight terminal allowing both:
* lines written one after another (normal terminal/console behaviour)
* fixed position text

Note: Requires an ANSI terminal. For Windows 7, please download https://github.com/downloads/adoxa/ansicon/ansi160.zip and run ansicon.exe -i to install it.
"""

from sys import stdout
import time

class zeroterm:
    def __init__(self, nrow=24, ncol=50):      # nrow, ncol determines the size of the scrolling (=normal terminal behaviour) part of the screen
        stdout.write("\x1b[2J")                # clear screen
        self.nrow = nrow
        self.ncol = ncol
        self.buf = []

    def write(self, s, x=None, y=None):        # if no x,y specified, normal console behaviour
        if x is not None and y is not None:    # if x,y specified, fixed text position
            self.movepos(x,y)
            print s
        else:
            if len(self.buf) < self.nrow:
                self.buf.append(s)
            else:
                self.buf[:-1] = self.buf[1:]
                self.buf[-1] = s
        
            for i, r in enumerate(self.buf):
                self.movepos(i+1,0)
                print r[:self.ncol].ljust(self.ncol)

    def movepos(self, row, col):
        stdout.write("\x1b[%d;%dH" % (row, col))


if __name__ == '__main__':
    # An exemple
    t = zeroterm()
    t.write('zeroterm', 1, 60)

    for i in range(1000):
        t.write(time.strftime("%H:%M:%S"), 3, 60)
        t.write("Hello %i" % i)
        time.sleep(0.1)