Upload data from stdin as a file with a specific name via cURL

From the cURL man page:

-F/--form

...

You can [...] explicitly change the name field of an file upload part by setting filename=, like this:

curl -F "file=@localfile;filename=nameinpost"

So this is exactly what I wanted. E.g.:

$ echo funfunfun | curl -F file=@-;filename=fun.txt http://etc/upload

I swear I had read the man pages a couple times before asking, but hadn't found that particular paragraph until now.

For protocols other than HTTP, and to use PUT for HTTP rather than form submission, use -T - with filename in URL:

echo bla-bla-bla | curl -T - ftp://user:[email protected]/foo.txt