Can somebody explain to me the intent of this dance?
(from ZEO/cache.py):
# Make sure the OS really saves enough bytes for the file.
self.f.seek(self.maxsize - 1)
self.f.write('x')
self.f.truncate()
The comment seems self-explanatory, except that I'm not sure what
"saves" means. Does the behavior vary on different filesystems? On
ext3 at least, a colleague just confirmed that this call "succeeds"
with self.maxsize ten times larger than the size of the filesystem.
It doesn't actually use many blocks though:
$ stat foo.txt
File: `foo.txt'
Size: 1000000000002 Blocks: 88 IO Block: 4096 regular file
Does this make future calls to self.f.write() faster somehow?
--
Paul Winkler
http://www.slinkp.com
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