Mike Gauland <mikelygee@gmail.com> writes:

> Mike Gauland <mikelygee <at> gmail.com> writes:
>
>> I can get an image if I evaluate the block manually (e.g., via 'C-c
> C-c' with
>> the cursor on the BEGIN block), but when I export the file the image
> is
>> invalid.
>
> I figured it out. I was getting extra carriage returns in the file. I've
> fixed
> them by setting "coding-system-for-write" to 'no-conversion within the
> (let).
>
> --Mike
>
I also encountered the same problem. But it seems not work perfectly by
letting "coding-system-for-write" be 'no-conversion. For example:
In my "test.org"

* test

#+BEGIN_SRC plantuml :file test.png
Alice -> Bob: Authentication Request
Bob --> Alice: Authentication Response
#+END_SRC


#+BEGIN_SRC plantuml :file test2.png
Alice2 -> Bob: Authentication Request
Bob --> Alice: Authentication Response
#+END_SRC

C-c C-c on the second src block does not create a right image.

So here is a new version of "ob-plantuml.el", which utilizes the io
redirection in shell directly.

Hope that it addresses the problem.