gracefully die if working dir is invalid at fork

In nearly every app, if the current working directory
disappears, the app becomes broken, sometimes subtly.  It can be
especially broken when preload_app is false (the default).

So just shut ourselves down to spare ourselves the
wasted CPU cycles on a dead app.

As a (hopefully) pleasant side effect, this allows
configurations with preload_app==false (the default) to do
application code reloads via SIGHUP (in addition to unicorn
config reloads).

1 files changed, 2 insertions, 0 deletions

diff --git a/SIGNALS b/SIGNALS
index 40f9c3d..c7c3833 100644
--- a/SIGNALS
+++ b/SIGNALS
@@ -7,6 +7,8 @@ processes are documented here as well.
 === Master Process
 
  * HUP - reload config file and gracefully restart all workers
+   If preload_app is false (the default), the application code
+   will be reloaded when workers are restarted as well.
 
  * INT/TERM - quick shutdown, kills all workers immediately