- name/filename parameters, the filename is just the serial counter. The file
- is saved in the directory set with -O (default is the current directory).
+ name/filename parameters, or the name/filename parameters contain forbidden
+ characters (null, slash, backslash) the filename is just the serial counter.
+</para>
+
+<para>
+ If the file doesn't have any extensions (no dots in the value of the
+ name/filename parameters, or the name is just the counter) the program tries
+ to guess an extension by looking up the content type in mime.types files
+ including .mime.types file in the user's home directory (if it exists). If
+ the file has an extension the program doesn't try to verify that it
+ corresponds to the content type.
+</para>
+
+<para>
+ The file is saved in the directory set with -O (default is the current
+ directory). The save options are proceeded before -e options so the user can
+ save the message that causes an error.