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.IX Title "LEI-DAEMON 8"
.TH LEI-DAEMON 8 1993-10-02 public-inbox.git "public-inbox user manual"
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.SH NAME
lei\-daemon \- technical information for local email interface daemon
.SH DESCRIPTION
.IX Header "DESCRIPTION"
This documentation is a high-level overview for developers and
administrators interested in how lei works.
.PP
lei-daemon is a background daemon which powers the \fBlei\fR\|(1)
command-line tool.  It may support virtual users and read-write
IMAP+JMAP APIs in the future.  It is designed to optimize shell
completion by avoiding module loading costs, monitor Maildirs
(and in the near future, IMAP folders) for changes.
.SS "worker processes"
.IX Subsection "worker processes"
Most commands cause lei-daemon to \fBfork\fR\|(2) new worker
processes to isolate and parallelize work.  lei-daemon is
significantly more aggressive than read-only
\&\fBpublic\-inbox\-daemon\fR\|(8) processes with regards to resource use
since it's not designed to support C10K/C100K scenarios.
.SS "file descriptor passing"
.IX Subsection "file descriptor passing"
FD passing is used to reduce IPC costs for bulk I/O when
importing large mboxes from stdin and dumping large mboxes
to stdout.
.SS SOCK_SEQPACKET
.IX Subsection "SOCK_SEQPACKET"
SOCK_SEQPACKET sockets are used for both communicating with
\&\fBlei\fR\|(1) and to internal workers.  SOCK_SEQPACKET guarantees
reliability (unlike SOCK_DGRAM), allows easy load distribution,
and saves developers the trouble of maintaining stream parsers.
.SS "file monitoring"
.IX Subsection "file monitoring"
Inotify or EVFILT_VNODE is used depending on the platform
to monitor Maildirs for changes and track keyword changes.
.PP
The listen socket (default: \f(CW\*(C`$XDG_RUNTIME_DIR/lei/5.seq.sock\*(C'\fR)
is also monitored, and the daemon will automatically shutdown
if it is unlinked.
.SH CONTACT
.IX Header "CONTACT"
Feedback welcome via plain-text mail to <mailto:meta@public\-inbox.org>
.PP
The mail archives are hosted at <https://public\-inbox.org/meta/> and
<http://4uok3hntl7oi7b4uf4rtfwefqeexfzil2w6kgk2jn5z2f764irre7byd.onion/meta/>
.SH COPYRIGHT
.IX Header "COPYRIGHT"
Copyright all contributors <mailto:meta@public\-inbox.org>
.PP
License: AGPL\-3.0+ <https://www.gnu.org/licenses/agpl\-3.0.txt>
.SH "SEE ALSO"
.IX Header "SEE ALSO"
\&\fBlei\-overview\fR\|(7), \fBlei\-daemon\-kill\fR\|(1), \fBlei\-daemon\-pid\fR\|(1)