splitmail - Split a large mail message into MIME-compliant partial messages

splitmail [-d] [-v] [-s splitsize] [-p prefix] [-i id-suffix] [file-name]

The splitmail program will take an email message and break it up into smaller pieces using the "message/partial" type defined by MIME(1), the proposed Internet standard for multimedia mail formats.

By default it will take the message either from standard input or the named file, and will produce a set of partial message files with names like "/tmp/split.1" for the first part, and so on. The prefix "/tmp/split." can be overridden using the "-p" option.

If the -d option is specified, the mail will actually be delivered. If -v is specified, the verbose flag will be passed to sendmail(8).

The -i option can be used to make splitmail generate the pieces with similar (but not identical) message-id fields, in a format which allows them to be easily correlated with one another and which end with the suffix provided on the command line after -i.

The default chunk size for splitting messages is 250000 at most sites, though this is also a compile-time option. This can be overridden with the -s switch, or with the environment variable SPLITSIZE.

Messages smaller than the chunk size will not be turned into partial messages, but will be written to a single file or delivered as a single message.

SPLITSIZE overrides the default chunk size. Setting SPLITSIZE to, say, 4000000 will effectively ensure that your messages are unlikely ever to be split, but it may cause them to be rejected by some mail transport software.

mailto(1), metamail(1), MIME(1), munpack(1)

If the size of the input is just on the fencepost, and if it is coming from a file rather than standard input, splitmail will sometimes estimate the number of parts wrong and will have to write out an extra part. This is harmless but annoying. It is especially annoying if the estimate was 2 but the real number was 1.

Copyright (c) 1992 Bell Communications Research, Inc. (Bellcore)

Permission to use, copy, modify, and distribute this material for any purpose and without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies, and that the name of Bellcore not be used in advertising or publicity pertaining to this material without the specific, prior written permission of an authorized representative of Bellcore. BELLCORE MAKES NO REPRESENTATIONS ABOUT THE ACCURACY OR SUITABILITY OF THIS MATERIAL FOR ANY PURPOSE. IT IS PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES.

Nathaniel S. Borenstein, Bellcore