[Pvfs2-users] corrupted output

[Chris Poultney]

All-

I'm having a problem where files written to a PVFS volume overwrite the 
beginning of the file after some output has already been generated, as 
if lseek() had been called mid-write. The overwriting behavior does not 
show up on a regular ext3 volume. Sample code is attached. I'd like to 
know if anyone can duplicate this behavior, because it looks like a bug.

Essentially what happens is this: given a large (1024+ character) 
string, I write some portion of the string using a C++ ostream, then 
write another line:

out << st.substr(0, N);
out << "done";

If N < 1024, everything is fine. If N >= 1024, "done" is written at the 
beginning of the file, overwriting what was there before.

I'd love to figure this out!

Cheers,
-crispy

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