Temporary files were not created in the temporary directory of the system, but…

Temporary files were not created in the temporary directory of the system, but in the current working directory.

h2/src/main/org/h2/store/fs/FileSystemDisk.java

@@ -178,7 +178,7 @@ public class FileSystemDisk extends FileSystem {
         String prefix = new File(name).getName();
         File dir;
         if (inTempDir) {
-            dir = null;
+            dir = new File(System.getProperty("java.io.tmpdir"));
         } else {
             dir = new File(name).getAbsoluteFile().getParentFile();
             IOUtils.mkdirs(dir);