diff --git a/desktop_version/src/FileSystemUtils.cpp b/desktop_version/src/FileSystemUtils.cpp
index 1a340f02..2ff8360d 100644
--- a/desktop_version/src/FileSystemUtils.cpp
+++ b/desktop_version/src/FileSystemUtils.cpp
@@ -186,6 +186,11 @@ bool FILESYSTEM_isFile(const char* filename)
 	|| stat.filetype == PHYSFS_FILETYPE_SYMLINK;
 }
 
+bool FILESYSTEM_isMounted(const char* filename)
+{
+	return PHYSFS_getMountPoint(filename) != NULL;
+}
+
 static bool FILESYSTEM_exists(const char *fname)
 {
 	return PHYSFS_exists(fname);
diff --git a/desktop_version/src/FileSystemUtils.h b/desktop_version/src/FileSystemUtils.h
index ddd163aa..f3aee2e3 100644
--- a/desktop_version/src/FileSystemUtils.h
+++ b/desktop_version/src/FileSystemUtils.h
@@ -13,6 +13,7 @@ char *FILESYSTEM_getUserSaveDirectory(void);
 char *FILESYSTEM_getUserLevelDirectory(void);
 
 bool FILESYSTEM_isFile(const char* filename);
+bool FILESYSTEM_isMounted(const char* filename);
 
 void FILESYSTEM_mount(const char *fname);
 void FILESYSTEM_loadZip(const char* filename);