Problem: If writing runs into a conversion error the backup file is
deleted. (Arseny Nasokin)
Solution: Don't delete the backup file is the file was overwritten and a
conversion error occurred. (Christian Brabandt, closes#4387)
Problem: Some tests fail on Solaris.
Solution: Skip writefile test. Fix path to libc.so. Improve test for Turkish
case change. (Libor Bukata, Bjorn Linse, closes#3403)
Problem: 'autowrite' takes effect when buffer is not to be written.
Solution: Don't write buffers that are not supposed to be written. (Even Q
Jones, closes#3391) Add tests for 'autowrite'.
Problem: Vim becomes unusable after opening new window in BufWritePre
event.
Solution: Call not_exiting(). (Martin Tournoij, closes#2205)
Also for "2q" when a help window is open. Add a test.
Problem: When making backups is disabled and conversion with iconv fails
the written file is truncated. (Luo Chen)
Solution: First try converting the file and write the file only when it did
not fail. (partly by Christian Brabandt)
Problem: writefile() continues after detecting an error.
Solution: Bail out as soon as an error is detected. (suggestions by Nikolai
Pavlov, closes#1476)
