reading last line in logfile with python

Asked Apr 05 '18 at 08:52

Active Apr 05 '18 at 08:52

Viewed 55 times

When trying to monitor a logfile for new lines with python I stumbled upon an issue.

What I try to do:

while True:
    file = open("log.txt", "r")
    file.seek(0,2)
    where = file.tell()
    line = file.readline()

    if not line:
        time.sleep(1)
        file.seek(where)
    else:
        *do stuff with line*

The line returned is always empty. I see why this is:

file.seek(0,2)

will always move the cursor to the end of the file and therefore there is no line after the cursor. But to watch the logfile for only new lines I will need to do this.

Can someone point me in the right direction on how to approach something like this.

asked Apr 05 '18 at 08:52

Franz

https://stackoverflow.com/questions/136168/get-last-n-lines-of-a-file-with-python-similar-to-tail does this look useable? – L_Church Apr 05 '18 at 08:56
1

Maybe this is helpful too: https://stackoverflow.com/questions/5419888/reading-from-a-frequently-updated-file – Cristian Ramon-Cortes Apr 05 '18 at 08:56

reading last line in logfile with python

0 Answers0