diff --git a/src/db/db/dbLayoutToNetlistReader.cc b/src/db/db/dbLayoutToNetlistReader.cc
index 127cbc4b7..706999790 100644
--- a/src/db/db/dbLayoutToNetlistReader.cc
+++ b/src/db/db/dbLayoutToNetlistReader.cc
@@ -60,7 +60,7 @@ typedef l2n_std_format::keys<true> skeys;
 typedef l2n_std_format::keys<false> lkeys;
 
 LayoutToNetlistStandardReader::LayoutToNetlistStandardReader (tl::InputStream &stream)
-  : m_stream (stream), m_path (stream.absolute_path ()), m_dbu (0.0),
+  : m_stream (stream), m_path (stream.absolute_file_path ()), m_dbu (0.0),
     m_progress (tl::to_string (tr ("Reading L2N database")), 1000)
 {
   m_progress.set_format (tl::to_string (tr ("%.0fk lines")));
diff --git a/src/db/db/dbNetlistSpiceReader.cc b/src/db/db/dbNetlistSpiceReader.cc
index 7e8563aa8..16684a39b 100644
--- a/src/db/db/dbNetlistSpiceReader.cc
+++ b/src/db/db/dbNetlistSpiceReader.cc
@@ -183,7 +183,7 @@ SpiceReaderStream::line_number () const
 std::string
 SpiceReaderStream::source () const
 {
-  return mp_stream->absolute_path ();
+  return mp_stream->absolute_file_path ();
 }
 
 bool
@@ -495,7 +495,7 @@ SpiceCircuitDict::read (tl::InputStream &stream)
     m_global_net_names.clear ();
     m_global_nets.clear ();
 
-    m_file_id = file_id (stream.absolute_path ());
+    m_file_id = file_id (stream.absolute_file_path ());
 
     while (! at_end ()) {
       read_card ();
diff --git a/src/db/db/dbTechnology.cc b/src/db/db/dbTechnology.cc
index 84bd4118e..d28d00739 100644
--- a/src/db/db/dbTechnology.cc
+++ b/src/db/db/dbTechnology.cc
@@ -479,10 +479,10 @@ std::string
 Technology::correct_path (const std::string &fp) const
 {
   std::string bp = base_path ();
-  if (bp.empty ()) {
+  if (bp.empty () || ! tl::InputStream::is_file_path (fp) || ! tl::InputStream::is_file_path (bp)) {
     return fp;
   } else {
-    return tl::relative_path (bp, fp);
+    return tl::relative_path (tl::InputStream::as_file_path (bp), tl::InputStream::as_file_path (fp));
   }
 }
 
@@ -494,7 +494,11 @@ Technology::load (const std::string &fn)
   xml_struct.parse (source, *this);
 
   //  use the tech file's path as the default base path
-  set_default_base_path (tl::absolute_path (fn));
+  if (tl::InputStream::is_file_path (fn)) {
+    set_default_base_path (tl::absolute_path (fn));
+  } else {
+    set_default_base_path (std::string ());
+  }
 
   set_tech_file_path (fn);
 }
@@ -515,10 +519,10 @@ Technology::build_effective_path (const std::string &p) const
     return p;
   }
 
-  if (tl::is_absolute (p)) {
+  if (tl::InputStream::is_absolute (p)) {
     return p;
   } else {
-    return tl::combine_path (bp, p);
+    return tl::InputStream::combine (bp, p);
   }
 }
 
diff --git a/src/lay/lay/layMainWindow.cc b/src/lay/lay/layMainWindow.cc
index a3f667791..f7444453c 100644
--- a/src/lay/lay/layMainWindow.cc
+++ b/src/lay/lay/layMainWindow.cc
@@ -2981,7 +2981,7 @@ void
 MainWindow::add_mru (const std::string &fn_rel, const std::string &tech)
 {
   std::vector <std::pair<std::string, std::string> > new_mru;
-  std::string fn (tl::InputStream::absolute_path (fn_rel));
+  std::string fn (tl::InputStream::absolute_file_path (fn_rel));
 
   for (auto mru = m_mru.begin (); mru != m_mru.end (); ++mru) {
     if (mru->first != fn /* delete non-existing files: && tl::is_readable (mru->first) */) {
@@ -3025,7 +3025,7 @@ MainWindow::add_to_other_mru (const std::string &fn_rel, const std::string &cfg)
   }
 
   std::vector <std::string> new_mru;
-  std::string fn (tl::InputStream::absolute_path (fn_rel));
+  std::string fn (tl::InputStream::absolute_file_path (fn_rel));
 
   for (auto mru = mru_ptr->begin (); mru != mru_ptr->end (); ++mru) {
     if (*mru != fn /* delete non-existing files: && tl::is_readable (*mru) */) {
diff --git a/src/lay/lay/laySession.cc b/src/lay/lay/laySession.cc
index bed76e234..72494b1d3 100644
--- a/src/lay/lay/laySession.cc
+++ b/src/lay/lay/laySession.cc
@@ -66,7 +66,7 @@ Session::fetch (const lay::MainWindow &mw)
     if (lh) {
       m_layouts.push_back (SessionLayoutDescriptor ());
       m_layouts.back ().name = *l;
-      m_layouts.back ().file_path = tl::InputStream::absolute_path (lh->filename ());
+      m_layouts.back ().file_path = tl::InputStream::absolute_file_path (lh->filename ());
       m_layouts.back ().load_options = lh->load_options ();
       m_layouts.back ().save_options = lh->save_options ();
       m_layouts.back ().save_options_valid = lh->save_options_valid ();
@@ -89,7 +89,7 @@ Session::fetch (const lay::MainWindow &mw)
 
       const rdb::Database *rdb = view->get_rdb (j);
       if (rdb && ! rdb->filename ().empty ()) {
-        view_desc.rdb_filenames.push_back (tl::InputStream::absolute_path (rdb->filename ()));
+        view_desc.rdb_filenames.push_back (tl::InputStream::absolute_file_path (rdb->filename ()));
       }
 
     }
@@ -98,7 +98,7 @@ Session::fetch (const lay::MainWindow &mw)
 
       const db::LayoutToNetlist *l2ndb = view->get_l2ndb (j);
       if (l2ndb && ! l2ndb->filename ().empty ()) {
-        view_desc.l2ndb_filenames.push_back (tl::InputStream::absolute_path (l2ndb->filename ()));
+        view_desc.l2ndb_filenames.push_back (tl::InputStream::absolute_file_path (l2ndb->filename ()));
       }
 
     }
diff --git a/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
index 893f83eb5..0b19845a1 100644
--- a/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFImporter.cc
@@ -1084,7 +1084,7 @@ LEFDEFReaderState::read_single_map_file (const std::string &path, std::map<std::
   tl::InputStream file_stream (file);
   tl::TextInputStream ts (file_stream);
 
-  tl::log << tl::to_string (tr ("Reading LEF/DEF map file")) << " " << file_stream.absolute_path ();
+  tl::log << tl::to_string (tr ("Reading LEF/DEF map file")) << " " << file_stream.absolute_file_path ();
 
   //  Purpose name to purpose code
   std::map<std::string, LayerPurpose> purpose_translation;
@@ -2011,7 +2011,7 @@ LEFDEFImporter::get_mask (long m)
 void 
 LEFDEFImporter::read (tl::InputStream &stream, db::Layout &layout, LEFDEFReaderState &state)
 {
-  tl::log << tl::to_string (tr ("Reading LEF/DEF file")) << " " << stream.absolute_path ();
+  tl::log << tl::to_string (tr ("Reading LEF/DEF file")) << " " << stream.absolute_file_path ();
 
   m_fn = stream.filename ();
 
diff --git a/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFPlugin.cc b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFPlugin.cc
index 8fe4c3fa5..3f04e2399 100644
--- a/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFPlugin.cc
+++ b/src/plugins/streamers/lefdef/db_plugin/dbLEFDEFPlugin.cc
@@ -120,7 +120,7 @@ LEFDEFReader::read_lefdef (db::Layout &layout, const db::LoadLayoutOptions &opti
 
   std::string base_path;
   if (! effective_options.paths_relative_to_cwd ()) {
-    base_path = tl::dirname (m_stream.absolute_path ());
+    base_path = tl::dirname (m_stream.absolute_file_path ());
   }
 
   db::LEFDEFReaderState state (&effective_options, layout, base_path);
@@ -179,7 +179,7 @@ LEFDEFReader::read_lefdef (db::Layout &layout, const db::LoadLayoutOptions &opti
 
     if (effective_options.read_lef_with_def ()) {
 
-      std::string input_dir = tl::absolute_path (m_stream.absolute_path ());
+      std::string input_dir = tl::absolute_path (m_stream.absolute_file_path ());
 
       if (tl::file_exists (input_dir)) {
 
diff --git a/src/rdb/rdb/rdb.cc b/src/rdb/rdb/rdb.cc
index 64f8192f4..125f18ec7 100644
--- a/src/rdb/rdb/rdb.cc
+++ b/src/rdb/rdb/rdb.cc
@@ -1786,7 +1786,7 @@ Database::load (std::string fn)
     reader.read (*this);
   }
 
-  set_filename (stream.absolute_path ());
+  set_filename (stream.absolute_file_path ());
   set_name (stream.filename ());
 
   reset_modified ();
diff --git a/src/tl/tl/tlFileUtils.cc b/src/tl/tl/tlFileUtils.cc
index 34aff09ae..342edd070 100644
--- a/src/tl/tl/tlFileUtils.cc
+++ b/src/tl/tl/tlFileUtils.cc
@@ -254,7 +254,6 @@ static std::vector<std::string> split_filename (const std::string &fn)
     const char *cp0 = cp;
     ++cp;
     while (*cp && *cp != '.') {
-      //  backslash escaping (ineffective on Windows because that is a path separator)
       if (*cp == '\\' && cp[1]) {
         ++cp;
       }
diff --git a/src/tl/tl/tlStream.cc b/src/tl/tl/tlStream.cc
index f83be7bfb..2d575fdc2 100644
--- a/src/tl/tl/tlStream.cc
+++ b/src/tl/tl/tlStream.cc
@@ -425,32 +425,124 @@ InputStream::~InputStream ()
   }
 }
 
-std::string InputStream::absolute_path (const std::string &abstract_path)
+std::string InputStream::absolute_file_path (const std::string &abstract_path)
 {
   //  TODO: align this implementation with InputStream ctor
 
   tl::Extractor ex (abstract_path.c_str ());
-#if defined(HAVE_QT)
   if (ex.test (":")) {
     return abstract_path;
-  } else
-#endif
-#if defined(HAVE_CURL) || defined(HAVE_QT)
-  if (ex.test ("http:") || ex.test ("https:")) {
-    return abstract_path;
-  } else
-#endif
-  if (ex.test ("pipe:")) {
+  } else if (ex.test ("http:") || ex.test ("https:") || ex.test ("pipe:") || ex.test ("data:")) {
     return abstract_path;
   } else if (ex.test ("file:")) {
     tl::URI uri (abstract_path);
-    return tl::absolute_path (uri.path ());
+    return tl::absolute_file_path (uri.path ());
   } else {
     return tl::absolute_file_path (abstract_path);
   }
 }
 
-const char * 
+bool InputStream::is_absolute (const std::string &abstract_path)
+{
+  //  TODO: align this implementation with InputStream ctor
+
+  tl::Extractor ex (abstract_path.c_str ());
+  if (ex.test (":")) {
+    return true;
+  } else if (ex.test ("http:") || ex.test ("https:") || ex.test ("pipe:") || ex.test ("data:")) {
+    return true;
+  } else if (ex.test ("file:")) {
+    tl::URI uri (abstract_path);
+    return tl::is_absolute (uri.path ());
+  } else {
+    return tl::is_absolute (abstract_path);
+  }
+}
+
+bool InputStream::is_file_path (const std::string &abstract_path)
+{
+  tl::Extractor ex (abstract_path.c_str ());
+  if (ex.test (":")) {
+    return false;
+  } else if (ex.test ("http:") || ex.test ("https:") || ex.test ("pipe:") || ex.test ("data:")) {
+    return false;
+  } else {
+    return true;
+  }
+}
+
+std::string InputStream::as_file_path (const std::string &abstract_path)
+{
+  tl::Extractor ex (abstract_path.c_str ());
+  if (ex.test (":")) {
+    return std::string ();
+  } else if (ex.test ("http:") || ex.test ("https:") || ex.test ("pipe:") || ex.test ("data:")) {
+    return std::string ();
+  } else if (ex.test ("file:")) {
+    tl::URI uri (abstract_path);
+    return uri.path ();
+  } else {
+    return abstract_path;
+  }
+}
+
+std::string InputStream::combine (const std::string &path1, const std::string &path2)
+{
+  if (is_absolute (path2)) {
+    return path2;
+  }
+
+  tl::Extractor ex (path1);
+  if (ex.test (":")) {
+    return path1 + "/" + path2;
+  } else if (ex.test ("pipe:") || ex.test ("data:")) {
+    //  ignore un-combinable first parts
+    return path2;
+  }
+
+  tl::URI uri1 (path1);
+  tl::URI uri2 (path2);
+
+  if (uri1.scheme ().empty ()) {
+    if (uri2.scheme ().empty ()) {
+      return tl::combine_path (path1, path2);
+    } else {
+      return tl::combine_path (path1, uri2.path ());
+    }
+  } else {
+    if (uri2.scheme ().empty ()) {
+      uri1.set_path (uri1.path () + "/" + tl::replaced (path2, "\\", "/"));
+    } else {
+      uri1.set_path (uri1.path () + "/" + uri2.path ());
+    }
+    return uri1.to_abstract_path ();
+  }
+}
+
+std::string InputStream::relative_path (const std::string &path1, const std::string &path2)
+{
+  //  TODO: align this implementation with InputStream ctor
+
+  tl::Extractor ex (path2);
+  if (ex.test (":")) {
+    return path2;
+  } else if (ex.test ("pipe:") || ex.test ("data:")) {
+    return path2;
+  }
+
+  tl::URI uri1 (path1);
+  tl::URI uri2 (path2);
+
+  //  NOTE: only file schemes are supported as of now
+  if ((uri1.scheme ().empty () || uri1.scheme () == "file") &&
+      (uri2.scheme ().empty () || uri2.scheme () == "file")) {
+    return tl::relative_path (uri1.path (), uri2.path ());
+  }
+
+  return path2;
+}
+
+const char *
 InputStream::get (size_t n, bool bypass_inflate)
 {
   //  if deflating, employ the deflate filter to get the data
diff --git a/src/tl/tl/tlStream.h b/src/tl/tl/tlStream.h
index c738c84ff..a69412aae 100644
--- a/src/tl/tl/tlStream.h
+++ b/src/tl/tl/tlStream.h
@@ -531,7 +531,7 @@ public:
    *
    *  Returns an empty string if no absolute path is available.
    */
-  std::string absolute_path () const
+  std::string absolute_file_path () const
   {
     return mp_delegate->absolute_path ();
   }
@@ -549,9 +549,34 @@ public:
   void close ();
 
   /**
-   *  @brief Gets the absolute path for a given URL
+   *  @brief Gets the absolute, abstract path for a given abstract path
    */
-  static std::string absolute_path (const std::string &path);
+  static std::string absolute_file_path (const std::string &apath);
+
+  /**
+   *  @brief Gets the absolute path for a given abstract path
+   */
+  static bool is_absolute (const std::string &apath);
+
+  /**
+   *  @brief Gets a value indicating whether the path is a file path
+   */
+  static bool is_file_path (const std::string &apath);
+
+  /**
+   *  @brief Gets the file path (no scheme) if it applies to the given abstract path
+   */
+  static std::string as_file_path (const std::string &apath);
+
+  /**
+   *  @brief Combines two abstract paths
+   */
+  static std::string combine (const std::string &apath1, const std::string &apath2);
+
+  /**
+   *  @brief Returns the relative abstract path of path2 vs. path1
+   */
+  static std::string relative_path (const std::string &apath1, const std::string &apath2);
 
   /**
    *  @brief Gets the base reader (delegate)
@@ -621,7 +646,7 @@ public:
 
   virtual std::string absolute_path () const
   {
-    return m_inflating_stream.absolute_path ();
+    return m_inflating_stream.absolute_file_path ();
   }
 
   virtual std::string filename () const
diff --git a/src/tl/unit_tests/tlStreamTests.cc b/src/tl/unit_tests/tlStreamTests.cc
index 156f276c2..8b310e6fc 100644
--- a/src/tl/unit_tests/tlStreamTests.cc
+++ b/src/tl/unit_tests/tlStreamTests.cc
@@ -479,3 +479,111 @@ TEST(RefuseToWrite)
   }
 }
 
+TEST(AbstractPathFunctions)
+{
+  EXPECT_EQ (tl::InputStream::absolute_file_path (""), tl::absolute_file_path ("."));
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("."), tl::absolute_file_path ("."));
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("pipe:xyz"), "pipe:xyz");
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("data:xyz"), "data:xyz");
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("https:xyz"), "https:xyz");
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("http:xyz"), "http:xyz");
+  EXPECT_EQ (tl::InputStream::absolute_file_path (":xyz"), ":xyz");
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("file:xyz"), tl::absolute_file_path ("xyz"));
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("xyz"), tl::absolute_file_path ("xyz"));
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("xyz/uvw"), tl::absolute_file_path ("xyz/uvw"));
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("/xyz/uvw"), "/xyz/uvw");
+  tl::file_utils_force_windows ();
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("xyz\\uvw"), tl::absolute_file_path ("xyz\\uvw"));
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("\\\\server\\xyz\\uvw"), "\\\\server\\xyz\\uvw");
+  EXPECT_EQ (tl::InputStream::absolute_file_path ("c:\\xyz\\uvw"), "c:\\xyz\\uvw");
+  tl::file_utils_force_reset ();
+
+  EXPECT_EQ (tl::InputStream::is_absolute (""), false);
+  EXPECT_EQ (tl::InputStream::is_absolute ("."), false);
+  EXPECT_EQ (tl::InputStream::is_absolute ("pipe:xyz"), true);
+  EXPECT_EQ (tl::InputStream::is_absolute ("data:xyz"), true);
+  EXPECT_EQ (tl::InputStream::is_absolute ("https:xyz"), true);
+  EXPECT_EQ (tl::InputStream::is_absolute ("http:xyz"), true);
+  EXPECT_EQ (tl::InputStream::is_absolute (":xyz"), true);
+  EXPECT_EQ (tl::InputStream::is_absolute ("file:xyz"), false);
+  EXPECT_EQ (tl::InputStream::is_absolute ("xyz"), false);
+  EXPECT_EQ (tl::InputStream::is_absolute ("xyz/uvw"), false);
+  EXPECT_EQ (tl::InputStream::is_absolute ("/xyz/uvw"), true);
+  tl::file_utils_force_windows ();
+  EXPECT_EQ (tl::InputStream::is_absolute ("xyz\\uvw"), false);
+  EXPECT_EQ (tl::InputStream::is_absolute ("\\\\server\\xyz\\uvw"), true);
+  EXPECT_EQ (tl::InputStream::is_absolute ("c:\\xyz\\uvw"), true);
+  tl::file_utils_force_reset ();
+
+  tl::file_utils_force_windows ();
+  EXPECT_EQ (tl::InputStream::combine ("a", ""), "a");
+  EXPECT_EQ (tl::InputStream::combine ("", "b"), "\\b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "b"), "a\\b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "b/c"), "a\\b/c");
+  EXPECT_EQ (tl::InputStream::combine ("a", "b\\c"), "a\\b\\c");
+  EXPECT_EQ (tl::InputStream::combine ("a", "data:abc"), "data:abc");
+  EXPECT_EQ (tl::InputStream::combine ("data:a", "b"), "b");
+  EXPECT_EQ (tl::InputStream::combine ("pipe:a", "b"), "b");
+  EXPECT_EQ (tl::InputStream::combine (":a", "b"), ":a/b");
+  EXPECT_EQ (tl::InputStream::combine ("https://a", "b"), "https://a/b");
+  EXPECT_EQ (tl::InputStream::combine ("https://a", "https:b"), "https:b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "https:b"), "https:b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "file:b"), "a\\b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "file:\\b"), "file:\\b");
+  EXPECT_EQ (tl::InputStream::combine ("file:a", "file:b"), "file:a/b");
+  EXPECT_EQ (tl::InputStream::combine ("file:a", "file:b/c"), "file:a/b/c");
+  EXPECT_EQ (tl::InputStream::combine ("file:a", "b\\c"), "file:a/b/c");
+  tl::file_utils_force_linux ();
+  EXPECT_EQ (tl::InputStream::combine ("a", "b"), "a/b");
+  EXPECT_EQ (tl::InputStream::combine ("", "b"), "/b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "b/c"), "a/b/c");
+  EXPECT_EQ (tl::InputStream::combine ("a", "data:abc"), "data:abc");
+  EXPECT_EQ (tl::InputStream::combine ("data:a", "b"), "b");
+  EXPECT_EQ (tl::InputStream::combine ("pipe:a", "b"), "b");
+  EXPECT_EQ (tl::InputStream::combine (":a", "b"), ":a/b");
+  EXPECT_EQ (tl::InputStream::combine ("https://a", "b"), "https://a/b");
+  EXPECT_EQ (tl::InputStream::combine ("https://a", "https:b"), "https:b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "https:b"), "https:b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "file:b"), "a/b");
+  EXPECT_EQ (tl::InputStream::combine ("a", "file:/b"), "file:/b");
+  EXPECT_EQ (tl::InputStream::combine ("file:a", "file:b"), "file:a/b");
+  EXPECT_EQ (tl::InputStream::combine ("file:a", "file:b/c"), "file:a/b/c");
+  EXPECT_EQ (tl::InputStream::combine ("file:a", "b/c"), "file:a/b/c");
+  tl::file_utils_force_reset ();
+
+  tl::file_utils_force_linux ();
+  EXPECT_EQ (tl::InputStream::relative_path ("", "file:/a/b/c"), "/a/b/c");
+  EXPECT_EQ (tl::InputStream::relative_path (".", "file:/a/b/c"), "/a/b/c");
+  EXPECT_EQ (tl::InputStream::relative_path ("https://x", "a/b/c"), "a/b/c");
+  EXPECT_EQ (tl::InputStream::relative_path ("file:/a/b", "file:/a/b/c"), "c");
+  EXPECT_EQ (tl::InputStream::relative_path ("/a/b", "/a/b/c"), "c");
+  EXPECT_EQ (tl::InputStream::relative_path ("/a/b", "/x/b/c"), "/x/b/c");
+  EXPECT_EQ (tl::InputStream::relative_path ("file:/a/b", "file:/a/b/c"), "c");
+  EXPECT_EQ (tl::InputStream::relative_path ("/a/b", "/a/b/c"), "c");
+  tl::file_utils_force_windows ();
+  EXPECT_EQ (tl::InputStream::relative_path ("/a/b", "/a/b/c"), "c");
+  EXPECT_EQ (tl::InputStream::relative_path ("/a/b", "\\a\\b\\c\\d"), "c\\d");
+  tl::file_utils_force_reset ();
+
+  EXPECT_EQ (tl::InputStream::is_file_path (""), true);
+  EXPECT_EQ (tl::InputStream::is_file_path (":abc"), false);
+  EXPECT_EQ (tl::InputStream::is_file_path ("pipe:abc"), false);
+  EXPECT_EQ (tl::InputStream::is_file_path ("data:abc"), false);
+  EXPECT_EQ (tl::InputStream::is_file_path ("http:abc"), false);
+  EXPECT_EQ (tl::InputStream::is_file_path ("file:abc"), true);
+  EXPECT_EQ (tl::InputStream::is_file_path ("a/b/c"), true);
+  tl::file_utils_force_windows ();
+  EXPECT_EQ (tl::InputStream::is_file_path ("a\\b\\c"), true);
+  tl::file_utils_force_reset ();
+
+  EXPECT_EQ (tl::InputStream::as_file_path (""), std::string ());
+  EXPECT_EQ (tl::InputStream::as_file_path (":abc"), std::string ());
+  EXPECT_EQ (tl::InputStream::as_file_path ("pipe:abc"), std::string ());
+  EXPECT_EQ (tl::InputStream::as_file_path ("data:abc"), std::string ());
+  EXPECT_EQ (tl::InputStream::as_file_path ("http:abc"), std::string ());
+  EXPECT_EQ (tl::InputStream::as_file_path ("file:abc"), "abc");
+  EXPECT_EQ (tl::InputStream::as_file_path ("a/b/c"), "a/b/c");
+  tl::file_utils_force_windows ();
+  EXPECT_EQ (tl::InputStream::as_file_path ("a\\b\\c"), "a\\b\\c");
+  tl::file_utils_force_reset ();
+}