What is wrong with this line of code?

Question

I've got this code I can't seem to get running:

 echo "digraph G{"; cat "$file"; echo "}" | dot -T png > graph.png

The terminal echoes all it should but gets stuck on the } symbol. I guess there's something wrong syntactically.

 Warning: <stdin>: syntax error in line 1 near '}'

Could you please be of quick help?

Answer 1

Presumably you meant to send all the output of the various statements to dot, like this:

{
  echo "digraph CG{"
  cat "$tmp"
  echo "}"
} | dot -T png > callgraph.png

Answer 2

With bash, you can collapse the echo;cat;echo

echo "digraph CG{$(< "$tmp")}" | dot ...

Or, if you like the extra newlines

printf 'digraph CG{\n%s\n}\n' "$(< "$tmp")" | dot ...