-.\" $Id: apropos.1,v 1.15 2011/12/25 16:53:51 schwarze Exp $
+.\" $Id: apropos.1,v 1.51 2020/10/01 22:50:00 schwarze Exp $
.\"
-.\" Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2011,2012,2014,2017,2018 Ingo Schwarze <schwarze@openbsd.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
-.Dd $Mdocdate: December 25 2011 $
+.Dd $Mdocdate: October 1 2020 $
.Dt APROPOS 1
.Os
.Sh NAME
-.Nm apropos
+.Nm apropos ,
+.Nm whatis
.Nd search manual page databases
.Sh SYNOPSIS
.Nm
+.Op Fl afk
.Op Fl C Ar file
-.Op Fl M Ar manpath
-.Op Fl m Ar manpath
+.Op Fl M Ar path
+.Op Fl m Ar path
+.Op Fl O Ar outkey
.Op Fl S Ar arch
.Op Fl s Ar section
.Ar expression ...
.Sh DESCRIPTION
The
-.Nm
-utility queries manual page databases generated by
-.Xr mandocdb 8 ,
-evaluating on
+.Nm apropos
+and
+.Nm whatis
+utilities query manual page databases generated by
+.Xr makewhatis 8 ,
+evaluating
.Ar expression
for each file in each database.
-Its arguments are as follows:
+By default, they display the names, section numbers, and description lines
+of all matching manuals.
+.Pp
+By default,
+.Nm
+searches for
+.Xr makewhatis 8
+databases in the default paths stipulated by
+.Xr man 1
+and uses case-insensitive extended regular expression matching
+over manual names and descriptions
+.Pq the Li \&Nm No and Li \&Nd No macro keys .
+Multiple terms imply pairwise
+.Fl o .
+.Pp
+.Nm whatis
+is a synonym for
+.Nm
+.Fl f .
+.Pp
+The options are as follows:
.Bl -tag -width Ds
+.It Fl a
+Instead of showing only the title lines, show the complete manual pages,
+just like
+.Xr man 1
+.Fl a
+would.
+If the standard output is a terminal device and
+.Fl c
+is not specified, use
+.Xr less 1
+to paginate them.
+In
+.Fl a
+mode, the options
+.Fl IKOTW
+described in the
+.Xr mandoc 1
+manual are also available.
.It Fl C Ar file
Specify an alternative configuration
.Ar file
in
.Xr man.conf 5
format.
-.It Fl M Ar manpath
+.It Fl f
+Search for all words in
+.Ar expression
+in manual page names only.
+The search is case-insensitive and matches whole words only.
+In this mode, macro keys, comparison operators, and logical operators
+are not available.
+.It Fl k
+Support the full
+.Ar expression
+syntax.
+It is the default for
+.Nm .
+.It Fl M Ar path
Use the colon-separated path instead of the default list of paths
searched for
-.Xr mandocdb 8
+.Xr makewhatis 8
databases.
Invalid paths, or paths without manual databases, are ignored.
-.It Fl m Ar manpath
+.It Fl m Ar path
Prepend the colon-separated paths to the list of paths searched
for
-.Xr mandocdb 8
+.Xr makewhatis 8
databases.
Invalid paths, or paths without manual databases, are ignored.
+.It Fl O Ar outkey
+Show the values associated with the key
+.Ar outkey
+instead of the manual descriptions.
.It Fl S Ar arch
-Search only for a particular architecture.
-.It Fl s Ar cat
-Search only for a manual section.
+Restrict the search to pages for the specified
+.Xr machine 1
+architecture.
+.Ar arch
+is case-insensitive.
+By default, pages for all architectures are shown.
+.It Fl s Ar section
+Restrict the search to the specified section of the manual.
+By default, pages from all sections are shown.
See
.Xr man 1
-for a listing of manual sections.
+for a listing of sections.
.El
.Pp
+The options
+.Fl chlw
+are also supported and are documented in
+.Xr man 1 .
+The options
+.Fl fkl
+are mutually exclusive and override each other.
+.Pp
An
.Ar expression
consists of search terms joined by logical operators
and
.Ar expr2
are true (logical
-.Qq and ) .
+.Sq and ) .
.It Ar expr1 Oo Fl o Oc Ar expr2
True if
.Ar expr1
and/or
.Ar expr2
evaluate to true (logical
-.Qq or ) .
+.Sq or ) .
.It Ar term
True if
.Ar term
is satisfied.
This has syntax
-.Li [key[,key]*(=~)]?val ,
-where operand
-.Cm key
+.Sm off
+.Oo
+.Op Ar key Op , Ar key ...
+.Pq Cm = | \(ti
+.Oc
+.Ar val ,
+.Sm on
+where
+.Ar key
is an
.Xr mdoc 7
macro to query and
-.Cm val
+.Ar val
is its value.
See
.Sx Macro Keys
for a list of available keys.
Operator
-.Li \&=
+.Cm =
evaluates a substring, while
-.Li \&~
-evaluates a regular expression.
+.Cm \(ti
+evaluates a case-sensitive extended regular expression.
.It Fl i Ar term
If
.Ar term
Has no effect on substring terms.
.El
.Pp
-By default,
-.Nm
-searches for
-.Xr mandocdb 8
-databases in the default paths stipulated by
-.Xr man 1 ,
-parses terms as case-sensitive regular expressions
-.Pq the Li \&~ operator
-over manual names and descriptions
-.Pq the Li \&Nm No and Li \&Nd No macro keys .
-Multiple terms imply pairwise
-.Fl o .
-Results are sorted by manual title, with output formatted as
+Results are sorted first according to the section number in ascending
+numerical order, then by the page name in ascending
+.Xr ascii 7
+alphabetical order, case-insensitive.
+.Pp
+Each output line is formatted as
.Pp
-.D1 title(sec) \- description
+.D1 name[, name...](sec) \- description
.Pp
Where
-.Qq title
-is the manual's title (note multiple manual names may exist for one
-title),
-.Qq sec
+.Dq name
+is the manual's name,
+.Dq sec
is the manual section, and
-.Qq description
+.Dq description
is the manual's short description.
If an architecture is specified for the manual, it is displayed as
.Pp
-.D1 title(cat/arch) \- description
+.D1 name(sec/arch) \- description
.Pp
Resulting manuals may be accessed as
.Pp
-.Dl $ man \-s sec title
+.Dl $ man \-s sec name
.Pp
If an architecture is specified in the output, use
.Pp
-.Dl $ man \-s sec \-S arch title
+.Dl $ man \-s sec \-S arch name
.Ss Macro Keys
Queries evaluate over a subset of
.Xr mdoc 7
macros indexed by
-.Xr mandocdb 8 .
+.Xr makewhatis 8 .
In addition to the macro keys listed below, the special key
.Cm any
may be used to match any available macro key.
.Bl -column "xLix" description -offset indent -compact
.It Li \&Nm Ta manual name
.It Li \&Nd Ta one-line manual description
+.It Li arch Ta machine architecture (case-insensitive)
+.It Li sec Ta manual section number
.El
.Pp
Sections and cross references:
.It Li \&Ox Ta Ox No version reference
.It Li \&Dx Ta Dx No version reference
.El
+.Pp
+In general, macro keys are supposed to yield complete results without
+expecting the user to consider actual macro usage.
+For example, results include:
+.Pp
+.Bl -tag -width 3n -offset 3n -compact
+.It Li \&Fa
+function arguments appearing on
+.Ic \&Fn
+lines
+.It Li \&Fn
+function names marked up with
+.Ic \&Fo
+macros
+.It Li \&In
+include file names marked up with
+.Ic \&Fd
+macros
+.It Li \&Vt
+types appearing as function return types and
+.It \&
+types appearing in function arguments in the SYNOPSIS
+.El
.Sh ENVIRONMENT
-.Bl -tag -width Ds
+.Bl -tag -width MANPAGER
+.It Ev MANPAGER
+Any non-empty value of the environment variable
+.Ev MANPAGER
+is used instead of the standard pagination program,
+.Xr less 1 ;
+see
+.Xr man 1
+for details.
+Only used if
+.Fl a
+or
+.Fl l
+is specified.
.It Ev MANPATH
-Colon-separated paths modifying the default list of paths searched for
-manual databases.
-Invalid paths, or paths without manual databases, are ignored.
+A colon-separated list of directories to search for manual pages; see
+.Xr man 1
+for details.
Overridden by
-.Fl M .
-If
-.Ev MANPATH
-begins with a
-.Sq \&: ,
-it is appended to the default list;
-else if it ends with
-.Sq \&: ,
-it is prepended to the default list; else if it contains
-.Sq \&:: ,
-the default list is inserted between the colons.
-If none of these conditions are met, it overrides the default list.
+.Fl M ,
+ignored if
+.Fl l
+is specified.
+.It Ev PAGER
+Specifies the pagination program to use when
+.Ev MANPAGER
+is not defined.
+If neither PAGER nor MANPAGER is defined,
+.Xr less 1
+is used.
+Only used if
+.Fl a
+or
+.Fl l
+is specified.
.El
.Sh FILES
.Bl -tag -width "/etc/man.conf" -compact
-.It Pa whatis.db
+.It Pa mandoc.db
name of the
-.Xr mandocdb 8
+.Xr makewhatis 8
keyword database
-.It Pa whatis.index
-name of the
-.Xr mandocdb 8
-filename database
.It Pa /etc/man.conf
default
.Xr man 1
.Ex -std
.Sh EXAMPLES
Search for
-.Qq mdoc
-as a substring and regular expression
-within each manual name and description:
+.Qq .cf
+as a substring of manual names and descriptions:
.Pp
-.Dl $ apropos mdoc
-.Dl $ apropos ~^mdoc$
+.Dl $ apropos =.cf
.Pp
Include matches for
-.Qq roff
+.Qq .cnf
and
-.Qq man
-for the regular expression case:
+.Qq .conf
+as well:
.Pp
-.Dl $ apropos ~^mdoc$ roff man
-.Dl $ apropos ~^mdoc$ \-o roff \-o man
+.Dl $ apropos =.cf =.cnf =.conf
.Pp
-Search for
+Search in names and descriptions using a case-sensitive regular expression:
+.Pp
+.Dl $ apropos \(aq\(tiset.?[ug]id\(aq
+.Pp
+Search for all manual pages in a given section:
+.Pp
+.Dl $ apropos \-s 9 \&.
+.Pp
+Search for manuals in the library section mentioning both the
.Qq optind
-and
+and the
.Qq optarg
-as variable names in the library category:
+variables:
+.Pp
+.Dl $ apropos \-s 3 Va=optind \-a Va=optarg
+.Pp
+Do exactly the same as calling
+.Nm whatis
+with the argument
+.Qq ssh :
+.Pp
+.Dl $ apropos \-\- \-i \(aqNm\(ti[[:<:]]ssh[[:>:]]\(aq
.Pp
-.Dl $ apropos \-s 3 Va~^optind \-a Va~^optarg$
+The following two invocations are equivalent:
+.Pp
+.D1 Li $ apropos -S Ar arch Li -s Ar section expression
+.Bd -ragged -offset indent
+.Li $ apropos \e( Ar expression Li \e)
+.Li -a arch\(ti^( Ns Ar arch Ns Li |any)$
+.Li -a sec\(ti^ Ns Ar section Ns Li $
+.Ed
.Sh SEE ALSO
.Xr man 1 ,
.Xr re_format 7 ,
-.Xr mandocdb 8
-.Sh AUTHORS
+.Xr makewhatis 8
+.Sh STANDARDS
+The
+.Nm
+utility is compliant with the
+.St -p1003.1-2008
+specification of
+.Xr man 1
+.Fl k .
+.Pp
+All options, the
+.Nm whatis
+command, support for logical operators, macro keys,
+substring matching, sorting of results, the environment variables
+.Ev MANPAGER
+and
+.Ev MANPATH ,
+the database format, and the configuration file
+are extensions to that specification.
+.Sh HISTORY
+Part of the functionality of
+.Nm whatis
+was already provided by the former
+.Nm manwhere
+utility in
+.Bx 1 .
The
.Nm
-utility was written by
-.An Kristaps Dzonsons ,
-.Mt kristaps@bsd.lv .
+and
+.Nm whatis
+utilities first appeared in
+.Bx 2 .
+They were rewritten from scratch for
+.Ox 5.6 .
+.Pp
+The
+.Fl M
+option and the
+.Ev MANPATH
+variable first appeared in
+.Bx 4.3 ;
+.Fl m
+in
+.Bx 4.3 Reno ;
+.Fl C
+in
+.Bx 4.4 Lite1 ;
+and
+.Fl S
+and
+.Fl s
+in
+.Ox 4.5
+for
+.Nm
+and in
+.Ox 5.6
+for
+.Nm whatis .
+The options
+.Fl acfhIKklOTWw
+appeared in
+.Ox 5.7 .
+.Sh AUTHORS
+.An -nosplit
+.An Bill Joy
+wrote
+.Nm manwhere
+in 1977 and the original
+.Bx
+.Nm
+and
+.Nm whatis
+in February 1979.
+The current version was written by
+.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv
+and
+.An Ingo Schwarze Aq Mt schwarze@openbsd.org .