Newbie question: files

[Niels Diepeveen]

William Wallace schreef:
> 
> I open a file "a+"
> 
> fd = open(foo, "a+")
> 
> I write some lines to it, taking care to flush after each write. I
> read some previously written lines by seeking back to them.
> 
> However, when I seek back to a previously written line, I cannot
> update any part of the line. The updates get written to the end of the
> file regardless of current position (known from fd.tell()).
> 
> What's up?

You asked for append mode, and you got it. If you don't want that, you
could do something like
open(foo, 'a').close()  # make sure the file exists, but don't destroy
it
fd = open(foo, 'r+')   # open existing file for read/write
fd.seek(0, 2)  # seek to end of file

-- 
Niels Diepeveen
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