[LyX/master] Amend ef42541d26: Missed to commit these

[Kornel Benko]

commit 4b052dec771af65808815eace8ec1f0cd90ed6b5
Author: Kornel Benko <kornel at lyx.org>
Date:   Mon Apr 13 13:39:33 2020 +0200

    Amend ef42541d26: Missed to commit these
---
 3rdparty/dtl/CMakeLists.txt |    5 ++++-
 src/LyX.cpp                 |   19 +++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletions(-)

diff --git a/3rdparty/dtl/CMakeLists.txt b/3rdparty/dtl/CMakeLists.txt
index 8b49bf4..3b31972 100644
--- a/3rdparty/dtl/CMakeLists.txt
+++ b/3rdparty/dtl/CMakeLists.txt
@@ -32,5 +32,8 @@ foreach(_t ${targets})
   add_man(${_t}.man)
 endforeach()
 
-install(TARGETS ${targets} DESTINATION ${LYX_UTILITIES_INSTALL_PATH})
+# Install dtl tools in this directory to omit possible packaging conflicts
+# if installing multiple lyx versions, each with own dtl executables
+get_data_destination(dest_data)
+install(TARGETS ${targets} DESTINATION "${CMAKE_INSTALL_PREFIX}/${dest_data}/extratools")
 install(FILES ${_manuals} DESTINATION ${LYX_MAN_DIR}/man1)
diff --git a/src/LyX.cpp b/src/LyX.cpp
index 20c5e83..d800d19 100644
--- a/src/LyX.cpp
+++ b/src/LyX.cpp
@@ -909,6 +909,25 @@ bool LyX::init()
 	if (package().build_support().empty())
 		prependEnvPath("PATH", package().binary_dir().absFileName());
 #endif
+	{
+		// Add the directory containing the dt2dv and dv2dt executables to the path
+		FileName dtldir;
+		if (!package().build_support().empty()) {
+			// dtl executables should be in the same dir ar tex2lyx
+			dtldir = package().binary_dir();
+		}
+		else {
+			dtldir = FileName(addName(package().system_support().absFileName(), "extratools"));
+		}
+#if defined(_WIN32)
+		string dtlexe = "dt2dv.exe";
+#else
+		string dtlexe = "dt2dv";
+#endif
+		FileName const dt2dv = FileName(addName(dtldir.absFileName(), dtlexe));
+		if (dt2dv.exists())
+			prependEnvPath("PATH", dtldir.absFileName());
+	}
 	if (!lyxrc.path_prefix.empty())
 		prependEnvPath("PATH", replaceEnvironmentPath(lyxrc.path_prefix));