* improvements in attachment / mime-part handling:

- add mu_util_play for 'playing' (opening) attachments; depends on xdg-open
  - stricter check for mu extract cmdline params
  - don't allow overwriting unless --overwrite was specified
  - mu extract now has a --play option to 'play' (open) attachments
  - added unit test to verify --overwrite
  - some cleanups in attachment/mime-part handling

src/mu-util.h

@@ -22,6 +22,7 @@
 
 #include <glib.h>
 #include <dirent.h>
+#include <sys/stat.h> /* for mode_t */
 
 G_BEGIN_DECLS
 
@@ -100,19 +101,30 @@ gboolean mu_util_check_dir (const gchar* path, gboolean readable,
  * create a writeable file and return its file descriptor (which
  * you'll need to close(2) when done with it.)
  * 
- * @param filename the filename
- * @param dir the target directory, or NULL for the current
+ * @param path the full path of the file to create
+ * @param the mode to open (ie. 0644 or 0600 etc., see chmod(3)
  * @param overwrite should we allow for overwriting existing files?
  * 
- * @return a file descriptor, or -1 in case of error. If it's a fily
- * system error, 'errno' may have more info. use 'close()' when done
+ * @return a file descriptor, or -1 in case of error. If it's a file
+ * system error, 'errno' may contain more info. use 'close()' when done
  * with the file descriptor
  */
-int mu_util_create_writeable_fd (const char* filename, const char* dir,
+int mu_util_create_writeable_fd (const char* path, mode_t mode,
 				 gboolean overwrite)
     G_GNUC_WARN_UNUSED_RESULT;
 
 
+/** 
+ * try to 'play' (ie., open with it's associated program) a
+ * file. depends on xdg-open to do the actual opening
+ * 
+ * @param path full path of the file to open
+ * 
+ * @return TRUE if it succeeded, FALSE otherwise
+ */
+gboolean mu_util_play (const char *path);
+
+
 /**
  * get the version of the xapian database (ie., the version of the
  * 'schema' we are using). If this version != MU_XAPIAN_DB_VERSION,