Comment 2 for bug 261595

Yes, the file in question is popstate.dat in the server folder of your mail

net_pop3_write_state() creates the whole file from scratch after we're done (or
David, write to a temp and then only delete the old and rename the new one if
we're succeeded writing? Would be save for the old UIDL, but UIDL of in this
session already downloaded messages would be lost too.
But I guess with this file format we can't to more intelligent writing.

BTW, what happens if a statement like
  outFileStream << host->user;
runs into a full disk?