To speed things up, I'd read more at a time. 
perl -pe'BEGIN { $/ = \(1024*1024); } s/\r//g;' file.in >file.out

[download]
But yeah, it will take time to copy 7GB.

In reply to Re^4: dos2ux shows cannot open file if it is greater than 2GB size by ikegami
in thread dos2ux shows cannot open file if it is greater than 2GB size by shan_emails

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