Question

I’m having a problem with a Python script I’m working on that searches a log file for occurances of a text string and if found prints them to another file, I have tried using break but that ends the process and I end up with only one entry in the other file, if I don’t use break, it applies the ending statement to all lines not containing the text, basically I want to end up with a logfile with all occurances of the text contained in it, if the text does not occur in any of the lines in the source logfile I want only one line printed to the new logfile saying that nothing was found, this is the code I am trying now –

with open("/var/log/syslog", "r") as vpnfile:
    for line in vpnfile:
        if "failed CHAP" in line:
            print (line,)
        elif "failed CHAP" not in line:    
            continue
        else:
            print ("Nadda")

Answer 1

Is this what you mean?

found = []
with open("/var/log/syslog", "r") as vpnfile:
    for line in vpnfile:
        if "failed CHAP" in line:
            found.append(line)
        # no need to check if "failed CHAP" is not in the line, since you
        # already know it's not there from the first test failing
if found:
    print(" ".join(found))
else:
    print("Nadda")