change lock format to let us detect and break stale locks. old style: symlink to pid new style: symlink to hostname:pid if lock code finds new-style lock, it breaks lock if locking pid is on same machine and pid is not alive. otherwise, lock is left alone. this makes locking code safe with old-style locks and with locks on other machines. new code makes server part of mercurial more robust in case machine crashes, power fails, or crazy user does kill -9.

#!/bin/sh

hg init
echo foo > a
hg add a
hg commit -m "1" -d "0 0"
hg verify
chmod -r .hg/data/a.d
hg verify 2>/dev/null || echo verify failed
chmod +r .hg/data/a.d
hg verify 2>/dev/null || echo verify failed
chmod -w .hg/data/a.d
echo barber > a
hg commit -m "2" -d "0 0" 2>/dev/null || echo commit failed