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This program generates a large amount of code and documentation for
all the daemon actions.

To add a new action there are only two files you need to change,
'actions.ml' to describe the interface, and daemon/<somefile>.c to
write the implementation.

After editing these files, build it (make -C generator) to regenerate
all the output files.  'make' will rerun this automatically when
necessary.

IMPORTANT: This program should NOT print any warnings at compile time
or run time.  If it prints warnings, you should treat them as errors.

OCaml tips:

(1) In emacs, install tuareg-mode to display and format OCaml code
correctly.  'vim' comes with a good OCaml editing mode by default.

(2) Read the resources at http://ocaml-tutorial.org/

(3) A module called 'Foo' is defined in one or two files called
'foo.mli' and 'foo.ml' (NB: lowercase first letter).  The *.mli file,
if present, defines the public interface for the module.  The *.ml
file is the implementation.  If the *.mli file is missing then
everything is exported.

Some notable files in this directory:

  actions.ml          The libguestfs API.
  structs.ml          Structures returned by the API.
  c.ml                Generate C API.
  <lang>.ml           Generate bindings for <lang>.
  main.ml             The main generator program.

Note about long descriptions:

When referring to another action, use the format C<guestfs_other>
(ie. the full name of the C function).  This will be replaced as
appropriate in other language bindings.  Apart from that, long
descriptions are just perldoc paragraphs.

Note about extending functions:

In general you cannot change the name, number of required arguments or
type of required arguments of a function, since this would break
backwards compatibility.

You may add another optional argument, *if* the function has >= 1
optional arguments already.  Add it at the end of the list.

You may add optional arguments to a function that doesn't have any.
However you *must* set the once_had_no_optargs flag to true, so that
the relevant backwards compatibility bindings can be added.