created using "filename" parameter from the Content-Disposition header, or
"name" parameter from the Content-Type header if one of those exist; a serial
counter is prepended to the filename to avoid collisions; if there are no
name/filename parameters, or the name/filename parameters contain forbidden
characters (null, slash, backslash) the filename is just the serial counter.
The file is saved in the directory set with -O (default is the current
created using "filename" parameter from the Content-Disposition header, or
"name" parameter from the Content-Type header if one of those exist; a serial
counter is prepended to the filename to avoid collisions; if there are no
name/filename parameters, or the name/filename parameters contain forbidden
characters (null, slash, backslash) the filename is just the serial counter.
The file is saved in the directory set with -O (default is the current