Problem: The function used to fork and exec for the extensible tables waits for the child to exit before reading the pipe for the output. Thus, if the child fills the pipe and blocks, the agent ends up deadlocked.
Solution: read from the pipe while waiting for the child to exit. The was the behavior in the 5.0.x and earlier lines. Patch: http://sourceforge.net/tracker/index.php?func=detail&aid=1052460&group_id=12694&atid=456380 Status: I'm in favor of it going in for 5.2, Dave wants to wait til 5.2.1. Summary of our exchange below: --------------------------------------------------- Dave Wrote: Dave> If it's due to the change in the handling of forking off sub-processes, Dave> then it will have been broken since 5.1 - i.e. for almost a year. Dave> If it's taken that long to come to light, then I don't really think Dave> this counts as a "show stopper". Robert> I consider any segfault or non-recoverable hang of the agent Robert> a show-stopper. I'd certainly agree that this is a significant bug, which definitely needs fixing. I wouldn't want you to get the wrong idea about that. I'm just saying that (IMO) the seriousness of a given problem has to be judged alongside the likelihood of it actually biting. And the fact that it's taken so long to come to light, would tend to suggest that this isn't necessarily an "urgent" fix. Dave> I'm very reluctant to jeopardize the 5.2 release at this late stage. Robert> Ok. Well, a proposed 'official patch' for 5.2 can be found at [snip] Well, the first thing to say is well done in tracking down this problem and coming up with a patch so quickly. If you're happy that this is likely to fix the problem, then it's definitely worth applying it to the 5.1.x line. I don't see any reason to hold off there. But having looked at the code of the patch, IMO it's suffficiently non-trivial that it would be better applied to the 5.2 line *after* the release freeze has been lifted. But of course I'm happy to defer to the general consensus, if that prefers to apply this to 5.2 straight away. -- Robert Story; NET-SNMP Junkie <http://www.net-snmp.org/> <irc://irc.freenode.net/#net-snmp> Archive: <http://sourceforge.net/mailarchive/forum.php?forum=net-snmp-coders> You are lost in a twisty maze of little standards, all different. ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click _______________________________________________ Net-snmp-coders mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/net-snmp-coders
