PHP Fatal error: Uncaught exception ‘RequestCore_Exception’ with message ‘The stream size for the streaming upload cannot be determined.’

While attempting to upload some large files (>2GB) to S3 yesterday, I ran across this error (on both sdk 1.2.3 and 1.3.2):

php s3-upload.php
Uploading file:  myfile.bak
PHP Fatal error:  Uncaught exception 'RequestCore_Exception' with message 'The stream size for the streaming upload cannot be determined.' in /home/josh/aws/sdk-1.2.3/lib/requestcore/requestcore.class.php:771
Stack trace:
#0 /home/josh/aws/sdk-1.2.3/services/s3.class.php(722): RequestCore->prep_request()
#1 /home/josh/aws/sdk-1.2.3/services/s3.class.php(1342): AmazonS3->authenticate('db-backup-resto...', Array)
#2 /home/josh/aws/bin/s3-upload.php(73): AmazonS3->create_object('db-backup-resto...', 'myfile.bak', Array)
#3 {main}
  thrown in /home/josh/aws/sdk-1.2.3/lib/requestcore/requestcore.class.php on line 771

I started to troubleshoot the error but as I had already successfully uploaded another smaller file, I suspected it was a problem with the size of the file I was uploading so I searched the AWS forums first. I found that there is a problem with uploading files greater than 2GB from a 32 bit machine due to the fact that fstat() and filesize() return the file size as 32-bit signed integer.

The fix is to use a 64 bit machine and perform the upload.