I am debugging a test case. I use Python's OptionParser (from optparse) to do some testing and one of the options is a HTTP request.
The input in this specific case for the http request was 269KB in size.
So my python program fails with "Argument list too long" (I verified that there was no other arguments passed, just the request and one more argument as expected by the option parser. When I throw away some of the request and reduce its size, things work fine. So I have a strong reason to believe the size of the request is causing my problems here.)
Is it possible for a HTTP request to be that big ?
If so how do I fix the OptionParser to handle this input?
A GET request, unlike a POST request, contains all its information in the url itself. This means you have an URL of 269KB, which is extremely long. 
Although there is no theoretical limit on the size allowed, many servers don't allow urls of over a couple of KB long and should return a 414 response code in that case. A safe limit is 2KB, although most modern software will allow a bit more than that. 
But still, for 269KB, use POST (or PUT if that is semantically more correct), which can contain larger chunks of data as the content of a request rather than the url.
Is a HTTP Get request of size 269KB allowed?