return with non-zero exit status on error

bin/gallery-dl

@@ -1,7 +1,6 @@
 #!/usr/bin/env python3
-# -*- coding: UTF-8 -*-
+# -*- coding: utf-8 -*-
 
+import sys
 import gallery_dl
-
-if __name__ == '__main__':
-    gallery_dl.main()
+sys.exit(gallery_dl.main())

gallery_dl/__init__.py

@@ -234,24 +234,28 @@ def main():
             if pformat and len(urls) > 1 and args.loglevel < logging.ERROR:
                 urls = progress(urls, pformat)
 
+            retval = 0
             for url in urls:
                 try:
                     log.debug("Starting %s for '%s'", jobtype.__name__, url)
                     if isinstance(url, util.ExtendedUrl):
                         for key, value in url.gconfig:
                             config.set(key, value)
                         with config.apply(url.lconfig):
-                            jobtype(url.value).run()
+                            retval |= jobtype(url.value).run()
                     else:
-                        jobtype(url).run()
+                        retval |= jobtype(url).run()
                 except exception.NoExtractorError:
                     log.error("No suitable extractor found for '%s'", url)
+                    retval |= 128
+            return retval
 
     except KeyboardInterrupt:
         sys.exit("\nKeyboardInterrupt")
     except BrokenPipeError:
         pass
-    except IOError as exc:
+    except OSError as exc:
         import errno
         if exc.errno != errno.EPIPE:
             raise
+    return 1

gallery_dl/__main__.py

@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
-# Copyright 2017 Mike Fährmann
+# Copyright 2017-2019 Mike Fährmann
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 2 as
@@ -17,4 +17,4 @@
 import gallery_dl
 
 if __name__ == "__main__":
-    gallery_dl.main()
+    sys.exit(gallery_dl.main())