Re-read an open file Python

Question

I have a script that reads a file and then completes tests based on that file however I am running into a problem because the file reloads after one hour and I cannot get the script to re-read the file after or at that point in time.

So:

• GETS NEW FILE TO READ
• Reads file
• performs tests on file
• GET NEW FILE TO READ (with same name - but that can change if it is part of a solution)
• Reads new file
• perform same tests on new file

Can anyone suggest a way to get Python to re-read the file?

Answer 1

Either seek to the beginning of the file

with open(...) as fin:     fin.read()   # read first time     fin.seek(0)  # offset of 0     fin.read()   # read again 

or open the file again (I'd prefer this way since you are otherwise keeping the file open for an hour doing nothing between passes)

with open(...) as fin:     fin.read()   # read first time  with open(...) as fin:     fin.read()   # read again 

Putting this together

while True:     with open(...) as fin:         for line in fin:             # do something      time.sleep(3600) 

Answer 2

You can move the cursor to the beginning of the file the following way:

file.seek(0) 

Then you can successfully read it.