Thank you everyone who helped me with this, especially jcwren and fastolfe.

In the end, it turned out to be a combination of factors involving UNIX/Windows CRLF issues, MIME encoding issues, an important and missing piece of HTTP syntax, assumptions by the cgi-script recieving the form, and general weirdness.

jcwren's working LWP code massively helped me decipher the issues involved (especially that damned missing Content-Length needed for the FILE parameter), to the point where I could get my non-LWP code working and look at the cgi-bin's output and go "WTF?" and figure out that it was expecting it to be mimencoded and on top of that, mimencoded in a Windows environment! But now the cgi's chop;chop;$_ = "$_\n"; is chomp;chomp;$_ = "$_\n"; instead and all is well with the world.

In reply to Re: amelinda's HTTP/MIME/file upload/not-a-cgi-but-a-client/minimal-module/perl problem by amelinda
in thread amelinda's HTTP/MIME/file upload/not-a-cgi-but-a-client/minimal-module/perl problem by amelinda

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.