If there is ONE bit of code that has caused us a huge amount of
consternation relative to it's use in nmh, it is the db/dbm code. It
is ONLY used by slocal to suppress messages with the same Message-Id.
I had a look. It looks up Message-ID, if found then it verbosely shows
its value, if it's not found then it stashes the `Delivery-Date' it
built earlier ready for next time.
I asked about removing this feature once, and I only got minor
pushback. While this API is part of POSIX, it doesn't seem like they
are standardized in terms of header files & library names.
POSIX, he say #include <ndbm.h>. And there's no special `-l foo'
required, unlike for some other include files.
That's what configure.ac tries first.
dnl Classic ndbm with no library required (eg NetBSD): try this
dnl first so we don't accidentally link in a pointless but harmless
dnl library in one of the later ndbm.h+libfoo tests:
dnl Berkeley DBv2 emulating ndbm: header in db.h, e.g., 32-bit Cygwin:
dnl Berkeley DBv1 emulating ndbm:
I'd rather make this support conditional; if we can't find a working
db/dbm library then we just don't support duplicate message
As long as slocal's -(no)suppressdup were errors so the user knew. And
a `make check' of it would be good because then of the `skip' in the
Would the big `nmh configuration' that's output at the end of
./configure then include whether ndbm.h support was found? It would be
handy if more were there, e.g. the recent `ICONV_ENABLED', as it's
something the user sees, might even read, and can easily pass onto us.
Also, the implementation seems to have the Message-Id database grow
without bounds, so I have to wonder how much it's being used.
Perhaps disk space has kept pace. Or the user sees the `possibly
corrupt file' error message and deletes it or otherwise fixes.
Given filesystems do a lot better at finding a filename in a large
directory these days, and stashing small files within the inode's space,
once wonders if Message-ID digested, and stuttered, would be sufficient.
Then the user can find(1) on -mtime, etc., to prune, as documented.