pycurl.error: (55, 'select/poll returned error')

[dieter]

Nagy László Zsolt <gandalf at shopzeus.com> writes:

> When calling  curl.perform() on a curl instance I get this:
>
> pycurl.error: (55, 'select/poll returned error')
> ....
> This error happens only if the file to be POST-ed is big enough. Last
> week files were under 1GB and everything went fine. Files above about
> 1GB cannot be sent over with curl.

Web services sometimes have limits about the allowed size of uploaded
files. I know about one web server application framework (Zope/ZServer)
that simply shuts down its communication channel when it receives
a too large file - such a behaviour can confuse the client.
Maybe, in your case, the server side, too, does something unexpected
when it receives large files?

"select/poll" by itself has nothing to do with the size of files.
It is used to get informed when one out a set of communication channels
is ready (again) for interaction. In principle, it should not fail --
unless something strange happens to the communication channels.