Merged revisions 179461 via svnmerge from

Merged revisions 179461 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r179461 | russell | 2009-03-02 16:58:18 -0600 (Mon, 02 Mar 2009) | 8 lines

Ensure that only one thread is calling ast_settimeout() on a channel at a time.

For example, with an IAX2 channel, you can have both the channel thread and the
chan_iax2 processing threads calling this function, and doing so twice at the
same time is a bad thing.

(Found in a debugging session with dvossel and mmichelson)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@179462 65c4cc65-6c06-0410-ace0-fbb531ad65f3