Merged revisions 48363 via svnmerge from

Merged revisions 48363 via svnmerge from
https://origsvn.digium.com/svn/asterisk/branches/1.4

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r48363 | russell | 2006-12-09 10:59:42 -0500 (Sat, 09 Dec 2006) | 8 lines

Use locking when accessing the registrations list.  This list is not actually
used very often, so the likelihood of there being a problem is pretty small,
but still possible.  For example, if the CLI command to list the registrations
was called at the same time that a reload was occurring and the registrations
list was getting destroyed and rebuilt, a crash could occur.

In passing, go ahead and convert this list to use the linked list macros.

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@48364 65c4cc65-6c06-0410-ace0-fbb531ad65f3