I have a problem with Mutt at the moment. I have a 4GL routine that creates some quite large output files and I want them to go in a single mail ideally. The total of these files is 21889119 (sum of zip files in Unix) and the message_size_limit in our Postfix config file is 25600000 so would expect these files to be sent. When I try to send them I get the following error :postdrop: warning: uid=502: Illegal seek              sendmail: fatal: progress(502): queue file error')which upon searching in Google comes back as a size error but to my mind I am almost 4M under the limit!Does Mutt add a lot of padding to the attachments or are there other switches to zip or Mutt that I should apply?
Mutt overheads or missing switches
email;mutt
The binary attachments need to be encoded as ascii and that typically expands them with 20-25%.You will have that expansion problem with any mailer, commandline or not. You can easily test that by using thunderbird and sending the file through Google (or your provider).