python get data from an already opened file -

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f=open("vmi","w") f.write("asdf") import os os.path.getsize("vmi") #0 byte f.close() os.path.getsize("vmi") # 4 bytes

where can find lost 4 bytes, on program execution, before file closed?

you try flush out data first:

f.flush()

why need this? well, os try buffer writes files performance reasons - lot slower write 1024 bytes 1 @ time write out whole buffer. so, whenever working file / pipe / socket kind of thing, keep in mind might buffering writes , need flush first.

when closed file, flushed automatically.


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