cgraph.h includes cdt.h as <cdt.h>, shoudl it not be "cdt.h" or <graphviz/cdt.h>?

[pliz]

Binary package hint: libgraphviz-dev

Hi guys,
Please, explain if this is not a bug. The file /usr/include/graphviz/cgraph.h contains the following line:
#include <cdt.h>
When I try to compile anything that includes this file (cgraph.h), gives me an error. For example
// start file test.c
#include <graphviz/cdt.h>
#include <graphviz/cgraph.h>
// end file test.c
Compile as:
gcc -lcgraph testcgraph.c
In file included from testcgraph.c:2:
/usr/include/graphviz/cgraph.h:20:18: error: cdt.h: No such file or directory

Should not the include line be changed to <graphviz/cdt.h> or "cdt.h", which would not have this problem?

Pertaining information:
libgraphviz-dev:
  Installed: 2.20.2-8ubuntu3
  Candidate: 2.20.2-8ubuntu3
  Version table:
 *** 2.20.2-8ubuntu3 0
        500 http://ubuntu.cs.unm.edu/ubuntu/ lucid/main Packages
        100 /var/lib/dpkg/status

Description: Ubuntu 10.04.1 LTS
Release: 10.04

[John Ellson (ellson)]

I don't consider myself an expert on setting up headers correctly for C programming, but my expectation here was that downstream users of installed graphviz libraries would use the pkg-config mechanism:

   pkg-config --cflags libcgraph

should produce the correct -I paths for your installation.

BTW graphviz-2.20 is old. graphviz-2.28 is available now from http://www.graphviz.org/