one problem with mosaic 2.0pre3, and ramifications

Marc Andreessen (
Wed, 8 Sep 93 01:48:34 -0500

A number of people have found that Mosaic 2.0pre3 will dump core when
talking to certain servers where such a server is both HTTP/1.0 and in
one's WWW_HOME (or equivalent) specification.

Such a coredump is triggered by the fact that the server is returning
an HTML document as type 'application/binary' when it should be
'text/html' -- i.e., the server is misconfigured. 2.0pre3 gets
confused (it's expecting something it can display, and it can't
display application/binary -- whereas it can display text/html, etc.)
and pukes.

While this coredump while be fixed in pre4, Mosaic and other HTTP/1.0
clients still won't know what to do with application/binary files
(besides simply offering to save them to disk).

So, the moral of the story is -- if you're running a HTTP/1.0 server
(Plexus 2.x, CERN httpd 2.x, ??... NCSA httpd 1.0 with HTTP/1.0
support is coming soon), now would be a very good time to check and
make sure that your server is properly configured and is returning
proper MIME types.

One way to do this, without Mosaic 2.0pre3, is to telnet to your
server on port 80 (or wherever) and ask for your home page:

GET /whatever HTTP/1.0 [return]
[blank line, return]

Then check the header that's returned; if it looks like this:

HTTP/1.0 200 Document follows
MIME-Version: 1.0
Content-Type: application/binary

....your server is misconfigured.