The csplit coreutil program lets me split a file into sections based on some delimiter. What I really want to do is split a file into sections based on a delimiter but forcing those sections to be at least b bytes in size, even if that means including multiple delimiters in most or all sections. An example would be that I have an mbox file (email messages) of 300 MB and containing 50,000 messages and I want to break it into 10 sections of at least 30 MB each (the tenth section would have to be a little smaller because there wouldn't be enough file left). I can do stuff like this to divide the file "mbox" into individual email messages, one per file... csplit -ksz mbox '/^From /' {*} ...but I can't figure out how to make the files bigger so that they include multiple delimiters. It seems like there ought to be a way to do this. Mike