Re: [9fans] 9pfuse and O_APPEND

[geoff@plan9.bell-labs.com]

The places that DMAPPEND is used most commonly are log files and mail
boxes.  In both cases, I don't want the decision of whether to
truncate or append left to the whims of some program.  I want writes
to append, by god, and DMAPPEND on actual disk-based file servers such
as fossil and fs does that.  (Yes, a malicious program could perhaps
clear DMAPPEND and truncate, but the more likely cause of disaster in
a system without DMAPPEND is someone forgetting to set a hypothetical
`append mode' on a fid or equivalent.  You only have to slip up once
to ruin someone's day.)