diff --git a/src/core/QuestFiles.cpp b/src/core/QuestFiles.cpp
index 6a4ef30ec..12236d3c2 100644
--- a/src/core/QuestFiles.cpp
+++ b/src/core/QuestFiles.cpp
@@ -84,7 +84,7 @@ void set_solarus_write_dir(const std::string& solarus_write_dir) {
   // First check that we can write in a directory.
   if (!PHYSFS_setWriteDir(get_base_write_dir().c_str())) {
      Debug::die(std::string("Cannot write in user directory '")
-         + get_base_write_dir().c_str() + "': " + PHYSFS_getLastError());
+         + get_base_write_dir().c_str() + "': " + PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));
   }
 
   // Create the directory.
@@ -93,7 +93,7 @@ void set_solarus_write_dir(const std::string& solarus_write_dir) {
   const std::string& full_write_dir = get_base_write_dir() + "/" + solarus_write_dir;
   if (!PHYSFS_setWriteDir(full_write_dir.c_str())) {
     Debug::die(std::string("Cannot set Solarus write directory to '")
-        + full_write_dir + "': " + PHYSFS_getLastError());
+        + full_write_dir + "': " + PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));
   }
 
   // The quest subdirectory may be new, create it if needed.
@@ -134,12 +134,12 @@ SOLARUS_API bool open_quest(const std::string& program_name, const std::string&
   std::string archive_quest_path_2 = quest_path + "/data.solarus.zip";
 
   const std::string& base_dir = PHYSFS_getBaseDir();
-  PHYSFS_addToSearchPath(dir_quest_path.c_str(), 1);   // data directory
-  PHYSFS_addToSearchPath(archive_quest_path_1.c_str(), 1); // data.solarus archive
-  PHYSFS_addToSearchPath(archive_quest_path_2.c_str(), 1); // data.solarus.zip archive
-  PHYSFS_addToSearchPath((base_dir + "/" + dir_quest_path).c_str(), 1);
-  PHYSFS_addToSearchPath((base_dir + "/" + archive_quest_path_1).c_str(), 1);
-  PHYSFS_addToSearchPath((base_dir + "/" + archive_quest_path_2).c_str(), 1);
+  PHYSFS_mount(dir_quest_path.c_str(), NULL, 1);   // data directory
+  PHYSFS_mount(archive_quest_path_1.c_str(), NULL, 1); // data.solarus archive
+  PHYSFS_mount(archive_quest_path_2.c_str(), NULL, 1); // data.solarus.zip archive
+  PHYSFS_mount((base_dir + "/" + dir_quest_path).c_str(), NULL, 1);
+  PHYSFS_mount((base_dir + "/" + archive_quest_path_1).c_str(), NULL, 1);
+  PHYSFS_mount((base_dir + "/" + archive_quest_path_2).c_str(), NULL, 1);
 
   // Set the engine root write directory.
   set_solarus_write_dir(SOLARUS_WRITE_DIR);
@@ -266,7 +266,18 @@ SOLARUS_API bool data_file_exists(const std::string& file_name,
     full_file_name = file_name;
   }
 
-  return PHYSFS_exists(full_file_name.c_str()) && !PHYSFS_isDirectory(full_file_name.c_str());
+  if(!PHYSFS_exists(full_file_name.c_str())) {
+    return false;
+  }
+
+  PHYSFS_Stat stats;
+  if(!PHYSFS_stat(full_file_name.c_str(),&stats)) {
+    Debug::die(std::string("Cannot stat file '") + full_file_name
+        + "': " + PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode())
+    );
+  }
+
+  return stats.filetype != PHYSFS_FILETYPE_DIRECTORY;
 }
 
 /**
@@ -305,7 +316,7 @@ SOLARUS_API std::string data_file_read(
   size_t size =  static_cast<size_t>(PHYSFS_fileLength(file));
   std::vector<char> buffer(size);
 
-  PHYSFS_read(file, buffer.data(), 1, (PHYSFS_uint32) size);
+  PHYSFS_readBytes(file, buffer.data(), (PHYSFS_uint32) size);
   PHYSFS_close(file);
 
   return std::string(buffer.data(), size);
@@ -325,14 +336,14 @@ SOLARUS_API void data_file_save(
   PHYSFS_file* file = PHYSFS_openWrite(file_name.c_str());
   if (file == nullptr) {
     Debug::die(std::string("Cannot open file '") + file_name
-        + "' for writing: " + PHYSFS_getLastError()
+        + "' for writing: " + PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode())
     );
   }
 
   // save the memory buffer
-  if (PHYSFS_write(file, buffer.data(), (PHYSFS_uint32) buffer.size(), 1) == -1) {
+  if (PHYSFS_writeBytes(file, buffer.data(), (PHYSFS_uint32) buffer.size()) == -1) {
     Debug::die(std::string("Cannot write file '") + file_name + "': "
-        + PHYSFS_getLastError());
+        + PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));
   }
   PHYSFS_close(file);
 }
@@ -403,7 +414,7 @@ SOLARUS_API void set_quest_write_dir(const std::string& quest_write_dir) {
   if (!quest_write_dir_.empty()) {
     // There was already a previous quest subdirectory: remove it from the
     // search path.
-    PHYSFS_removeFromSearchPath(PHYSFS_getWriteDir());
+    PHYSFS_unmount(PHYSFS_getWriteDir());
   }
 
   quest_write_dir_ = quest_write_dir;
@@ -413,7 +424,7 @@ SOLARUS_API void set_quest_write_dir(const std::string& quest_write_dir) {
   std::string full_write_dir = get_base_write_dir() + "/" + solarus_write_dir_;
   if (!PHYSFS_setWriteDir(full_write_dir.c_str())) {
     Debug::die(std::string("Cannot set Solarus write directory to '")
-        + full_write_dir + "': " + PHYSFS_getLastError());
+        + full_write_dir + "': " + PHYSFS_getErrorByCode(PHYSFS_getLastErrorCode()));
   }
 
   if (!quest_write_dir.empty()) {
@@ -426,7 +437,7 @@ SOLARUS_API void set_quest_write_dir(const std::string& quest_write_dir) {
     PHYSFS_setWriteDir(full_write_dir.c_str());
 
     // Also allow the quest to read savegames, settings and data files there.
-    PHYSFS_addToSearchPath(PHYSFS_getWriteDir(), 0);
+    PHYSFS_mount(PHYSFS_getWriteDir(),NULL, 0);
   }
 }
 
@@ -446,7 +457,11 @@ SOLARUS_API std::string get_base_write_dir() {
 #if defined(SOLARUS_OSX) || defined(SOLARUS_IOS)
   return get_user_application_support_directory();
 #else
+  //Silence the deprecation warning since we must rely on getUserDir behaviour for compatibility
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
   return std::string(PHYSFS_getUserDir());
+#pragma GCC diagnostic pop
 #endif
 }