If you are asking whether you can update a file in place, the answer is "yes" - look up "lseek" in the Python documentation (module os, under "File Descriptor Operations".Hi,
the example provided by Vishnu is quite close to what I want but it still required me to write all the data back to the file.
Is there any way where I can just write a particular line?
However, you asked about replacing one line with another of a different length: since this will mean changing the offsets of all subsequent bytes you have no way to do this other than writing out the whole content of the file following the modification. You would also have to ensure that you truncated the file to the correct length.
In general, although they don't make it obvious that they are doing so most programs that "change" files (text editors and the like) are really writing new copies.
regards Steve -- Steve Holden +1 703 861 4237 +1 800 494 3119 Holden Web LLC http://www.holdenweb.com/ Python Web Programming http://pydish.holdenweb.com/
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