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+Running
+=======
+
+Just start `./setup.sh`. It will do the following:
+
+ 1. download apt sources and apt-file data for the amd64 Debian sid snapshot at
+    20141211T041251Z and store them in a directory tree rooted at
+    `./debian-sid-amd64`
+ 2. go through all binary packages which have a file `DEBIAN/triggers` in their
+    control archive (the list is stored in the file `control_triggers_packages`)
+    and for each package:
+       2.0. download and unpack its control archive
+       2.1. store all interest-await file triggers in the file `interested-file`
+       2.2. store all interest-await explicit triggers in the file `interested-explicit`
+       2.1. store all activate-await file triggers in the file `activated-file`
+       2.1. store all activate-await explicit triggers in the file `activated-explicit`
+       2.6. remove the downloaded binary package and unpacked control archive
+ 3. go through `interested-file` and for each line:
+       3.1. calculate the dependency closure for the binary package and for
+            each package in the closure:
+               3.1.1. use `apt-file` to get all files of the package
+               3.1.2. check if the current file trigger matches any file in the package
+               3.1.3. store any hits in the file `result-file`
+ 4. go through `interested-file` and for each line:
+       4.1. calculate the dependency closure for the binary package and for
+            each package in the closure:
+               4.1.1. check if the package activates the current file trigger
+               3.1.3. append any hits to the file `result-file`
+ 5. go through `interested-explicit` and for each line:
+       5.1. calculate the dependency closure for the binary package and for
+            each package in the closure:
+               5.1.1. check if the package activate the current explicit trigger
+               3.1.3. store any hits in the file `result-explicit`
+
+Files
+=====
+
+control_triggers_packages
+-------------------------
+
+The currently known files that ship a `DEBIAN/triggers` file in their control
+metadata. In the future, this list should be autogenerated.
+
+interested-file
+---------------
+
+Associates binary packages to file triggers they are interested in. The first
+column is the binary package, the second column is either `interest` or
+`interest-await` and the last column the path they are interested in.
+
+interested-explicit
+-------------------
+
+Associates binary packages to explicit triggers they are interested in. The
+first column is the binary package, the second column is either `interest` or
+`interest-await` and the last column the name of the explicit trigger they are
+interested in.
+
+activated-file
+--------------
+
+Associates binary packages to file triggers they activate. The first column is
+the binary package, the second column is either `activate` or `activate-await`
+and the last column the path they activate.
+
+activate-explicit
+-----------------
+
+Associates binary packages to explicit triggers they activate. The first column
+is the binary package, the second column is either `activate` or
+`activate-await` and the last column the explicit trigger they activate.
+
+result-file
+-----------
+
+Associates binary packages with other binary packages they can form a file
+trigger cycle with. The first column is the binary package containing the file
+trigger, the second column is the file trigger, the third column is a binary
+package providing a path that triggers the binary package in the first column,
+the fourth column is the triggering path of provided by the binary package in
+the third column.
+
+result-explicit
+---------------
+
+Associates binary packages with other binary packages they can form an explicit
+trigger cycle with. The first column is the binary package interested in the
+explicit trigger, the second column is the name of the explicit trigger, the
+third column is the binary package activating the trigger.