Question

The output of top command in Linux like bellow:

Tasks: 158 total, 1 running, 157 sleeping, 0 stopped, 0 zombie
Cpu(s): 6.3%us, 3.2%sy, 0.0%ni, 89.9%id, 0.2%wa, 0.0%hi, 0.2%si,
0.0%st Mem: 8264212k total, 2637492k used, 5626720k free, 299884k buffers Swap: 4192924k total, 0k used, 4192924k free,
2010332k cached

PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
7178 mysql 15 0 52876 31m 4680 S 21.3 0.4 308:12.04 mysqld
2262 www 16 0 28092 11m 4764 S 4.0 0.1 2:02.31 php-cgi
2110 www 16 0 27956 11m 4888 S 3.7 0.1 2:04.51 php-cgi
2005 www 16 0 28680 12m 4872 S 3.0 0.2 2:04.10 php-cgi
1955 www 16 0 28476 12m 5220 S 2.7 0.1 2:06.51 php-cgi
2030 www 16 0 28260 11m 4872 S 2.0 0.1 2:05.27 php-cgi
7044 www 15 0 24348 19m 932 S 0.7 0.2 1:58.38 nginx

Only part of the content changes constantly.

I can only output a single line keeps changing constantly without newline:

import  sys
import  time

if __name__ == '__main__':
    i = 0
    while True:
        sys.stdout.write('i = %d.\r' % i)
        sys.stdout.flush()
        time.sleep(1)
        i += 1

I want to know how to output multiline like the top command(keeps changing constantly without newline).

Sorry, My English is poor. Hope that makes sense.

Thanks,
Qi

Answer 1

You will need to use a library for handling the interaction with the console, e.g. http://docs.python.org/howto/curses.html