Python and reading lines

Question

When i run an .exe file it prints stuff out to the screen. I don't know the specific line of where i want printed out but is there a way I can get python to print the next line after one that says "Summary" ? I know that is in there when it prints and I need the info right after. Thanks!

Answer 1

actually

program.exe | grep -A 1 Summary

would do your job.

Answer 2

Really simple Python solution:

def getSummary(s):
    return s[s.find('\nSummary'):]

This returns everything after the first instance of Summary
If you need to be more specific, I'd recommend regular expressions.

Answer 3

If the exe prints to screen then pipe that output to a text file. I have assumed the exe is on windows, then from the command line:

myapp.exe > output.txt

And your reasonably robust python code would be something like:

try:
    f = open("output.txt", "r")
    lines = f.readlines()
    # Using enumerate gives a convenient index.
    for i, line in enumerate(lines) :
        if 'Summary' in line :
            print lines[i+1]
            break                # exit early
# Python throws this if 'Summary' was there but nothing is after it.
except IndexError, e :
    print "I didn't find a line after the Summary"
# You could catch other exceptions, as needed.
finally :
    f.close()