[mythtv-commits] Ticket #10249: config.xml gets truncated due to race condition when rewriting it on every application run

[MythTV]

#10249: config.xml gets truncated due to race condition when rewriting it on every
application run
-------------------------------------+-------------------------------------
 Reporter:  dekarl@…                 |           Type:  Bug Report -
   Status:  new                      |  General
Milestone:  unknown                  |       Priority:  minor
  Version:  Trunk Head               |      Component:  MythTV - General
 Keywords:                           |       Severity:  medium
                                     |  Ticket locked:  0
-------------------------------------+-------------------------------------
 Symptom in any logfile:
 {{{
 2012-01-09 21:56:59.715916 E  Error parsing:
 /home/mythtv/.mythtv/config.xml at line: 1  column: 1
 2012-01-09 21:56:59.715921 E  Error Msg: unexpected end of file
 }}}

 See the diagnosis between 18:00 and 21:00 at
 http://irc.mythtv.org/ircLog/channel/4/2011-12-29:18:05

 It appears that every application **rewrites** the config file on every
 run which can lead to silent truncation when the application is killed at
 the right time.

 Possible solutions:
 * only write the config file when it has been changed
 * rewrite the config writing to make the race condition impossible (like
 writing to tempfile and move that over the old one)

-- 
Ticket URL: <http://code.mythtv.org/trac/ticket/10249>
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