inotify: raise correct error if server is already started in a deep repository
When path is too long to be an Unix socket address, we create a socket in a
temporary directory and link from the long path to the shorter one.
But checks in server code at startup were insufficient in this case, and used
to raise an unclear "tried linking .hg/inotify.sock to a temporary socket but
.hg/inotify.sock already exists"
$ mkdir a
$ cd a
$ hg init
$ echo 123 > a
$ hg add a
$ hg commit -m "a" -u a
$ cd ..
$ mkdir b
$ cd b
$ hg init
$ echo 321 > b
$ hg add b
$ hg commit -m "b" -u b
$ hg pull ../a
pulling from ../a
searching for changes
abort: repository is unrelated
[255]
$ hg pull -f ../a
pulling from ../a
searching for changes
warning: repository is unrelated
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg heads
changeset: 1:9a79c33a9db3
tag: tip
parent: -1:000000000000
user: a
date: Thu Jan 01 00:00:00 1970 +0000
summary: a
changeset: 0:01f8062b2de5
user: b
date: Thu Jan 01 00:00:00 1970 +0000
summary: b