[BitBucket user: Luiz Eduardo Valmont]
[BitBucket date: 2019-01-20.14:27:37]

This affects at least 1.3.2.

I've noticed something odd. When I run Orthanc without specifying the DCMDICTPATH environment variable, I get this:

2019-01-18T23:53:15.024560 INFO [7f65477f6700] PluginsManager.cpp:172 Tagging image with the following command: /usr/bin/dcmodify -i "(0069,0020)=RDSL" -i "(0069,2001)=131" /var/orthanc/tmp/d5dc-b3ee-1f98-4372
E: DcmDataDictionary: Cannot open file: /usr/share/libdcmtk12
W: no data dictionary loaded, check environment variable: DCMDICTPATH
W: DcmItem: Length of element (7fe0,0010) is not a multiple of 2 (VR=OW)

But when I do specify it, I get this:

2019-01-18T23:23:12.804872 INFO [7fccab845e40] FromDcmtkBridge.cpp:206 Using DCTMK version: 362
2019-01-18T23:23:12.856255 WARNING [7fccab845e40] FromDcmtkBridge.cpp:164 Loading the external DICOM dictionary "/usr/share/libdcmtk12/diconde.dic:/usr/share/libdcmtk12/acrnema.dic:/usr/share/libdcmtk12/private.dic:/usr/share/libdcmtk12/dicom.dic/dicom.dic"
E: DcmDataDictionary: Cannot open file: /usr/share/libdcmtk12/diconde.dic:/usr/share/libdcmtk12/acrnema.dic:/usr/share/libdcmtk12/private.dic:/usr/share/libdcmtk12/dicom.dic/dicom.dic
2019-01-18T23:23:12.857114 ERROR [7fccab845e40] main.cpp:1324 Uncaught exception, stopping now: [Internal error] (code -1)
2019-01-18T23:23:12.857236 WARNING [7fccab845e40] main.cpp:1357 Orthanc has stopped

The second time around, as it seems, Orthanc tries to append a "/dicom" to the value of DCMDICTPATH treating it as purely a directory only to abort right after that. But DCMTK itself will try to conform to its specification (ref: https://support.dcmtk.org/docs/file_envvars.html).

Upon close inspection of the FromDdcmtkBridge.cpp, I found this:


```
#!python

      const char* env = std::getenv(DCM_DICT_ENVIRONMENT_VARIABLE);
      if (env != NULL)
      {
        path = std::string(env);
      }

      LoadExternalDictionary(*locker, path, "dicom.dic");

      if (loadPrivateDictionary)
      {
        LoadExternalDictionary(*locker, path, "private.dic");
      }
      else
      {
        LOG(INFO) << "The dictionary of private tags has not been loaded";
      }

```

And from Resources/WebAssembly/dcdict.h:


```
#!python

/// environment variable pointing to the data dictionary file
#define DCM_DICT_ENVIRONMENT_VARIABLE   "DCMDICTPATH"
```


Oddly enough, it started after I switched to compiling Orthanc with USE_SYSTEM_DCMTK=ON.