.\"	$Id$
.\"
.\" Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate$
.Dt MANDOCDB 8
.Os
.Sh NAME
.Nm mandocdb
.Nd index UNIX manuals
.Sh SYNOPSIS
.Nm
.Op Fl av
.Op Ar dir ...
.Nm
.Op Fl v
.Fl d Ar dir
.Op Ar
.Nm
.Op Fl v
.Fl u Ar dir
.Op Ar
.Sh DESCRIPTION
The
.Nm
utility extracts keywords from
.Ux
manuals and indexes them in a
.Sx Keyword Database
and
.Sx Index Database
for fast retrieval.
.Pp
By default,
.Nm
creates databases in each
.Ar dir
using the files
.Sm off
.Sy man Ar section Li /
.Op Ar arch Li /
.Ar title . section
.Sm on
and
.Sm off
.Sy cat Ar section Li /
.Op Ar arch Li /
.Ar title . Sy 0
.Sm on
in that directory;
existing databases are truncated.
If
.Ar dir
is not provided,
.Nm
uses the default paths stipulated by
.Xr man 1 .
.Pp
The arguments are as follows:
.Bl -tag -width Ds
.It Fl a
Use all directories and files found below
.Ar dir ... .
.It Fl d Ar dir
Merge (remove and re-add)
.Ar
to the database in
.Ar dir
without truncating it.
.It Fl u Ar dir
Remove
.Ar
from the database in
.Ar dir
without truncating it.
.It Fl v
Verbose operation.
Use once to display all files added or removed and twice for keywords as
well.
.El
.Pp
If fatal parse errors are encountered while parsing, the offending file
is printed to stderr, omitted from the index, and the parse continues
with the next input file.
.Ss Index Database
The index database,
.Pa mandoc.index ,
is a
.Xr recno 3
database with record values consisting of
.Pp
.Bl -enum -compact
.It
the string
.Cm mdoc ,
.Cm man ,
or
.Cm cat
to indicate the file type,
.It
the filename,
.It
the manual section,
.It
the manual title,
.It
the architecture
.Pq often empty ,
.It
and the description.
.El
.Pp
Each of the above is NUL-terminated.
.Pp
Both the manual section and description may be zero-length if the record
is unassigned.
Entries are sequentially-numbered, but the filenames are unordered.
.Ss Keyword Database
The keyword database,
.Pa mandoc.db ,
is a
.Xr btree 3
database of NUL-terminated keywords (record length is non-zero string
length plus one) mapping to a 8-byte binary field consisting of the
keyword type and source
.Sx Index Database
record number.
The type, a 32-bit bit-mask in host order, consists of the following
fields:
.Pp
.Bl -tag -width Ds -offset indent -compact
.It Li 0x01
The name of a manual page as given in the NAME section.
.It Li 0x02
A function prototype name as given in the SYNOPSIS section.
.It Li 0x04
A utility name as given in the SYNOPSIS section.
.It Li 0x08
An include file as given in the SYNOPSIS section.
.It Li 0x10
A variable name as given in the SYNOPSIS section.
.It Li 0x20
A standard as given in the STANDARDS section.
.It Li 0x40
An author as given in the AUTHORS section.
.It Li 0x80
A configuration as given in the SYNOPSIS section.
.It Li 0x100
Free-form descriptive text as given in the NAME section.
.It Li 0x200
Cross-links between manuals.
Listed as the link name, then a period, then the link section.
If the link has no section, the period terminates the string.
.It Li 0x400
Path reference as given in the FILES section.
.It Li 0x800
Environment variable as given in the ENVIRONMENT section.
.It Li 0x1000
Error codes as given in the ERRORS section.
.El
.Pp
The last four bytes are a host-ordered record number within the
.Sx Index Database .
.Pp
The
.Nm
utility is
.Ud
.Sh IMPLEMENTATION NOTES
The time to construct a new database pair grows linearly with the
number of keywords in the input files.
However, removing or updating entries with
.Fl u
or
.Fl d ,
respectively, grows as a multiple of the index length and input size.
.Sh FILES
.Bl -tag -width Ds
.It Pa mandoc.db
A
.Xr btree 3
keyword database mapping keywords to a type and file reference in
.Pa mandoc.index .
.It Pa mandoc.index
A
.Xr recno 3
database of indexed file-names.
.El
.Sh EXIT STATUS
The
.Nm
utility exits with one of the following values:
.Pp
.Bl -tag -width Ds -compact
.It 0
No errors occurred.
.It 5
Invalid command line arguments were specified.
No input files have been read.
.It 6
An operating system error occurred, for example memory exhaustion or an
error accessing input files.
Such errors cause
.Nm
to exit at once, possibly in the middle of parsing or formatting a file.
The output databases are corrupt and should be removed .
.El
.Sh SEE ALSO
.Xr man 1 ,
.Xr mandoc 1 ,
.Xr btree 3 ,
.Xr recno 3
.Sh AUTHORS
The
.Nm
utility was written by
.An Kristaps Dzonsons ,
.Mt kristaps@bsd.lv .