workaround popen trouble on windows

footer_with_songinfo.ly

@@ -10,7 +10,9 @@
         (assoc-ref author "death_year")
         (assoc-ref author "organization")
       )
-      "unbekannt")))
+      (if (string-null? authorId)
+          "unbekannt"
+          authorId))))
 
 #(define (find-author-ids-by contributionType authors)
   (if authors

scm/yaml_parser.scm

@@ -4,7 +4,7 @@
 (define (yml-file->scm filename)
   (if windows?
     (let* ((tmpdir (or (getenv "TMPDIR") (getenv "TEMP") "/tmp"))
-            (port (mkstemp (string-append tmpdir file-name-separator-string (basename filename) "-XXXXXX") "r"))
+            (port (mkstemp (string-append tmpdir "\\" (basename filename) "-XXXXXX") "r"))
             (tmpfilepath (port-filename port))
             (python_code (string-append "import sys, yaml, json; f = open('" tmpfilepath "', 'w'); f.write(json.dumps(yaml.safe_load(open('" filename "')))); f.close()"))
             (status (system (string-append "py -X utf8 -c \"" python_code "\"")))