+.It POSIX.1 before the Single UNIX Specification
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-p1003.1-88
+.St -p1003.1-88
+.It \-p1003.1
+.St -p1003.1
+.br
+The original POSIX standard, based on ANSI C.
+.Pp
+.It \-p1003.1-90
+.St -p1003.1-90
+.It \-iso9945-1-90
+.St -iso9945-1-90
+.br
+The first update of POSIX.1.
+.Pp
+.It \-p1003.1b-93
+.St -p1003.1b-93
+.It \-p1003.1b
+.St -p1003.1b
+.br
+Real-time extensions.
+.Pp
+.It \-p1003.1c-95
+.St -p1003.1c-95
+.br
+POSIX thread interfaces.
+.Pp
+.It \-p1003.1i-95
+.St -p1003.1i-95
+.br
+Technical Corrigendum.
+.Pp
+.It \-p1003.1-96
+.St -p1003.1-96
+.It \-iso9945-1-96
+.St -iso9945-1-96
+.br
+Includes POSIX.1-1990, 1b, 1c, and 1i.
+.El
+.It X/Open Portability Guide version 4 and related standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-xpg3
+.St -xpg3
+.br
+An XPG4 precursor, published in 1989.
+.Pp
+.It \-p1003.2
+.St -p1003.2
+.It \-p1003.2-92
+.St -p1003.2-92
+.It \-iso9945-2-93
+.St -iso9945-2-93
+.br
+An XCU4 precursor.
+.Pp
+.It \-p1003.2a-92
+.St -p1003.2a-92
+.br
+Updates to POSIX.2.
+.Pp
+.It \-xpg4
+.St -xpg4
+.br
+Based on POSIX.1 and POSIX.2, published in 1992.
+.El
+.It Single UNIX Specification version 1 and related standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-susv1
+.St -susv1
+.It \-xpg4.2
+.St -xpg4.2
+.br
+This standard was published in 1994.
+It was used as the basis for UNIX 95 certification.
+The following three refer to parts of it.
+.Pp
+.It \-xsh4.2
+.St -xsh4.2
+.Pp
+.It \-xcurses4.2
+.St -xcurses4.2
+.Pp
+.It \-p1003.1g-2000
+.St -p1003.1g-2000
+.br
+Networking APIs, including sockets.
+.Pp
+.It \-svid4
+.St -svid4 ,
+.br
+Published in 1995.
+.El
+.It Single UNIX Specification version 2 and related standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-susv2
+.St -susv2
+This Standard was published in 1997
+and is also called X/Open Portability Guide version 5.
+It was used as the basis for UNIX 98 certification.
+The following refer to parts of it.
+.Pp
+.It \-xbd5
+.St -xbd5
+.Pp
+.It \-xsh5
+.St -xsh5
+.Pp
+.It \-xcu5
+.St -xcu5
+.Pp
+.It \-xns5
+.St -xns5
+.It \-xns5.2
+.St -xns5.2
+.El
+.It Single UNIX Specification version 3
+.Pp
+.Bl -tag -width "-p1003.1-2001" -compact
+.It \-p1003.1-2001
+.St -p1003.1-2001
+.It \-susv3
+.St -susv3
+.br
+This standard is based on C99, SUSv2, POSIX.1-1996, 1d, and 1j.
+It is also called X/Open Portability Guide version 6.
+It is used as the basis for UNIX 03 certification.
+.Pp
+.It \-p1003.1-2004
+.St -p1003.1-2004
+.br
+The second and last Technical Corrigendum.
+.El
+.It Single UNIX Specification version 4
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-p1003.1-2008
+.St -p1003.1-2008
+.It \-susv4
+.St -susv4
+.br
+This standard is also called
+X/Open Portability Guide version 7.
+.El
+.It Other standards
+.Pp
+.Bl -tag -width "-p1003.1g-2000" -compact
+.It \-ieee754
+.St -ieee754
+.br
+Floating-point arithmetic.
+.Pp
+.It \-iso8601
+.St -iso8601
+.br
+Representation of dates and times, published in 1988.
+.Pp
+.It \-iso8802-3
+.St -iso8802-3
+.br
+Ethernet local area networks.
+.Pp
+.It \-ieee1275-94
+.St -ieee1275-94
+.El
+.El
+.Ss \&Sx
+Reference a section or subsection in the same manual page.
+The referenced section or subsection name must be identical to the
+enclosed argument, including whitespace.
+.Pp
+Examples:
+.Dl \&.Sx MANUAL STRUCTURE
+.Pp
+See also
+.Sx \&Sh
+and
+.Sx \&Ss .
+.Ss \&Sy
+Request a boldface font.
+.Pp
+This is most often used to indicate importance or seriousness (not to be
+confused with stress emphasis, see
+.Sx \&Em ) .
+When none of the semantic macros fit, it is also adequate for syntax
+elements that have to be given or that appear verbatim.
+.Pp
+Examples:
+.Bd -literal -compact -offset indent
+\&.Sy Warning :
+If
+\&.Sy s
+appears in the owner permissions, set-user-ID mode is set.
+This utility replaces the former
+\&.Sy dumpdir
+program.
+.Ed
+.Pp
+See also
+.Sx \&Bf ,
+.Sx \&Em ,
+.Sx \&Li ,
+and
+.Sx \&No .
+.Ss \&Ta
+Table cell separator in
+.Sx \&Bl Fl column
+lists; can only be used below
+.Sx \&It .
+.Ss \&Tn
+Supported only for compatibility, do not use this in new manuals.
+Even though the macro name
+.Pq Dq tradename
+suggests a semantic function, historic usage is inconsistent, mostly
+using it as a presentation-level macro to request a small caps font.
+.Ss \&Ud
+Supported only for compatibility, do not use this in new manuals.
+Prints out
+.Dq currently under development.
+.Ss \&Ux
+Supported only for compatibility, do not use this in new manuals.
+Prints out
+.Dq Ux .
+.Ss \&Va
+A variable name.
+.Pp
+Examples:
+.Dl \&.Va foo
+.Dl \&.Va const char *bar ;
+.Pp
+For function arguments and parameters, use
+.Sx \&Fa
+instead.
+For declarations of global variables in the
+.Em SYNOPSIS
+section, use
+.Sx \&Vt .
+.Ss \&Vt
+A variable type.
+.Pp
+This is also used for indicating global variables in the
+.Em SYNOPSIS
+section, in which case a variable name is also specified.
+Note that it accepts
+.Sx Block partial-implicit
+syntax when invoked as the first macro on an input line in the
+.Em SYNOPSIS
+section, else it accepts ordinary
+.Sx In-line
+syntax.
+In the former case, this macro starts a new output line,
+and a blank line is inserted in front if there is a preceding
+function definition or include directive.
+.Pp
+Examples:
+.Dl \&.Vt unsigned char
+.Dl \&.Vt extern const char * const sys_signame[] \&;
+.Pp
+For parameters in function prototypes, use
+.Sx \&Fa
+instead, for function return types
+.Sx \&Ft ,
+and for variable names outside the
+.Em SYNOPSIS
+section
+.Sx \&Va ,
+even when including a type with the name.
+See also
+.Sx MANUAL STRUCTURE .
+.Ss \&Xc
+Close a scope opened by
+.Sx \&Xo .
+.Ss \&Xo
+Extend the header of an
+.Sx \&It
+macro or the body of a partial-implicit block macro
+beyond the end of the input line.
+This macro originally existed to work around the 9-argument limit
+of historic
+.Xr roff 7 .
+.Ss \&Xr
+Link to another manual
+.Pq Qq cross-reference .
+Its syntax is as follows:
+.Pp
+.D1 Pf \. Sx \&Xr Ar name section
+.Pp
+Cross reference the
+.Ar name
+and
+.Ar section
+number of another man page.
+.Pp
+Examples:
+.Dl \&.Xr mandoc 1
+.Dl \&.Xr mandoc 1 \&;
+.Dl \&.Xr mandoc 1 \&Ns s behaviour
+.Sh MACRO SYNTAX
+The syntax of a macro depends on its classification.
+In this section,
+.Sq \-arg
+refers to macro arguments, which may be followed by zero or more
+.Sq parm
+parameters;
+.Sq \&Yo
+opens the scope of a macro; and if specified,
+.Sq \&Yc
+closes it out.
+.Pp
+The
+.Em Callable
+column indicates that the macro may also be called by passing its name
+as an argument to another macro.
+For example,
+.Sq \&.Op \&Fl O \&Ar file
+produces
+.Sq Op Fl O Ar file .
+To prevent a macro call and render the macro name literally,
+escape it by prepending a zero-width space,
+.Sq \e& .
+For example,
+.Sq \&Op \e&Fl O
+produces
+.Sq Op \&Fl O .
+If a macro is not callable but its name appears as an argument
+to another macro, it is interpreted as opaque text.
+For example,
+.Sq \&.Fl \&Sh
+produces
+.Sq Fl \&Sh .
+.Pp
+The
+.Em Parsed
+column indicates whether the macro may call other macros by receiving
+their names as arguments.
+If a macro is not parsed but the name of another macro appears
+as an argument, it is interpreted as opaque text.
+.Pp
+The
+.Em Scope
+column, if applicable, describes closure rules.
+.Ss Block full-explicit
+Multi-line scope closed by an explicit closing macro.
+All macros contains bodies; only
+.Sx \&Bf
+and
+.Pq optionally
+.Sx \&Bl
+contain a head.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
+\(lBbody...\(rB
+\&.Yc
+.Ed
+.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXX" -offset indent
+.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
+.It Sx \&Bd Ta \&No Ta \&No Ta closed by Sx \&Ed
+.It Sx \&Bf Ta \&No Ta \&No Ta closed by Sx \&Ef
+.It Sx \&Bk Ta \&No Ta \&No Ta closed by Sx \&Ek
+.It Sx \&Bl Ta \&No Ta \&No Ta closed by Sx \&El
+.It Sx \&Ed Ta \&No Ta \&No Ta opened by Sx \&Bd
+.It Sx \&Ef Ta \&No Ta \&No Ta opened by Sx \&Bf
+.It Sx \&Ek Ta \&No Ta \&No Ta opened by Sx \&Bk
+.It Sx \&El Ta \&No Ta \&No Ta opened by Sx \&Bl
+.El
+.Ss Block full-implicit
+Multi-line scope closed by end-of-file or implicitly by another macro.
+All macros have bodies; some
+.Po
+.Sx \&It Fl bullet ,
+.Fl hyphen ,
+.Fl dash ,
+.Fl enum ,
+.Fl item
+.Pc
+don't have heads; only one
+.Po
+.Sx \&It
+in
+.Sx \&Bl Fl column
+.Pc
+has multiple heads.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead... \(lBTa head...\(rB\(rB
+\(lBbody...\(rB
+.Ed
+.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXXXXXXXXX" -offset indent
+.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
+.It Sx \&It Ta \&No Ta Yes Ta closed by Sx \&It , Sx \&El
+.It Sx \&Nd Ta \&No Ta \&No Ta closed by Sx \&Sh
+.It Sx \&Nm Ta \&No Ta Yes Ta closed by Sx \&Nm , Sx \&Sh , Sx \&Ss
+.It Sx \&Sh Ta \&No Ta Yes Ta closed by Sx \&Sh
+.It Sx \&Ss Ta \&No Ta Yes Ta closed by Sx \&Sh , Sx \&Ss
+.El
+.Pp
+Note that the
+.Sx \&Nm
+macro is a
+.Sx Block full-implicit
+macro only when invoked as the first macro
+in a
+.Em SYNOPSIS
+section line, else it is
+.Sx In-line .
+.Ss Block partial-explicit
+Like block full-explicit, but also with single-line scope.
+Each has at least a body and, in limited circumstances, a head
+.Po
+.Sx \&Fo ,
+.Sx \&Eo
+.Pc
+and/or tail
+.Pq Sx \&Ec .
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB
+\(lBbody...\(rB
+\&.Yc \(lBtail...\(rB
+
+\&.Yo \(lB\-arg \(lBparm...\(rB\(rB \(lBhead...\(rB \
+\(lBbody...\(rB \&Yc \(lBtail...\(rB
+.Ed
+.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent
+.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
+.It Sx \&Ac Ta Yes Ta Yes Ta opened by Sx \&Ao
+.It Sx \&Ao Ta Yes Ta Yes Ta closed by Sx \&Ac
+.It Sx \&Bc Ta Yes Ta Yes Ta closed by Sx \&Bo
+.It Sx \&Bo Ta Yes Ta Yes Ta opened by Sx \&Bc
+.It Sx \&Brc Ta Yes Ta Yes Ta opened by Sx \&Bro
+.It Sx \&Bro Ta Yes Ta Yes Ta closed by Sx \&Brc
+.It Sx \&Dc Ta Yes Ta Yes Ta opened by Sx \&Do
+.It Sx \&Do Ta Yes Ta Yes Ta closed by Sx \&Dc
+.It Sx \&Ec Ta Yes Ta Yes Ta opened by Sx \&Eo
+.It Sx \&Eo Ta Yes Ta Yes Ta closed by Sx \&Ec
+.It Sx \&Fc Ta Yes Ta Yes Ta opened by Sx \&Fo
+.It Sx \&Fo Ta \&No Ta \&No Ta closed by Sx \&Fc
+.It Sx \&Oc Ta Yes Ta Yes Ta closed by Sx \&Oo
+.It Sx \&Oo Ta Yes Ta Yes Ta opened by Sx \&Oc
+.It Sx \&Pc Ta Yes Ta Yes Ta closed by Sx \&Po
+.It Sx \&Po Ta Yes Ta Yes Ta opened by Sx \&Pc
+.It Sx \&Qc Ta Yes Ta Yes Ta opened by Sx \&Oo
+.It Sx \&Qo Ta Yes Ta Yes Ta closed by Sx \&Oc
+.It Sx \&Re Ta \&No Ta \&No Ta opened by Sx \&Rs
+.It Sx \&Rs Ta \&No Ta \&No Ta closed by Sx \&Re
+.It Sx \&Sc Ta Yes Ta Yes Ta opened by Sx \&So
+.It Sx \&So Ta Yes Ta Yes Ta closed by Sx \&Sc
+.It Sx \&Xc Ta Yes Ta Yes Ta opened by Sx \&Xo
+.It Sx \&Xo Ta Yes Ta Yes Ta closed by Sx \&Xc
+.El
+.Ss Block partial-implicit
+Like block full-implicit, but with single-line scope closed by the
+end of the line.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBbody...\(rB \(lBres...\(rB
+.Ed
+.Bl -column "MacroX" "CallableX" "ParsedX" -offset indent
+.It Em Macro Ta Em Callable Ta Em Parsed
+.It Sx \&Aq Ta Yes Ta Yes
+.It Sx \&Bq Ta Yes Ta Yes
+.It Sx \&Brq Ta Yes Ta Yes
+.It Sx \&D1 Ta \&No Ta \&Yes
+.It Sx \&Dl Ta \&No Ta Yes
+.It Sx \&Dq Ta Yes Ta Yes
+.It Sx \&En Ta Yes Ta Yes
+.It Sx \&Op Ta Yes Ta Yes
+.It Sx \&Pq Ta Yes Ta Yes
+.It Sx \&Ql Ta Yes Ta Yes
+.It Sx \&Qq Ta Yes Ta Yes
+.It Sx \&Sq Ta Yes Ta Yes
+.It Sx \&Vt Ta Yes Ta Yes
+.El
+.Pp
+Note that the
+.Sx \&Vt
+macro is a
+.Sx Block partial-implicit
+only when invoked as the first macro
+in a
+.Em SYNOPSIS
+section line, else it is
+.Sx In-line .
+.Ss Special block macro
+The
+.Sx \&Ta
+macro can only be used below
+.Sx \&It
+in
+.Sx \&Bl Fl column
+lists.
+It delimits blocks representing table cells;
+these blocks have bodies, but no heads.
+.Bl -column "MacroX" "CallableX" "ParsedX" "closed by XXXX" -offset indent
+.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Scope
+.It Sx \&Ta Ta Yes Ta Yes Ta closed by Sx \&Ta , Sx \&It
+.El
+.Ss In-line
+Closed by the end of the line, fixed argument lengths,
+and/or subsequent macros.
+In-line macros have only text children.
+If a number (or inequality) of arguments is
+.Pq n ,
+then the macro accepts an arbitrary number of arguments.
+.Bd -literal -offset indent
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB \(lBres...\(rB
+
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB \(lBargs...\(rB Yc...
+
+\&.Yo \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN
+.Ed
+.Bl -column "MacroX" "CallableX" "ParsedX" "Arguments" -offset indent
+.It Em Macro Ta Em Callable Ta Em Parsed Ta Em Arguments
+.It Sx \&%A Ta \&No Ta \&No Ta >0
+.It Sx \&%B Ta \&No Ta \&No Ta >0
+.It Sx \&%C Ta \&No Ta \&No Ta >0
+.It Sx \&%D Ta \&No Ta \&No Ta >0
+.It Sx \&%I Ta \&No Ta \&No Ta >0
+.It Sx \&%J Ta \&No Ta \&No Ta >0
+.It Sx \&%N Ta \&No Ta \&No Ta >0
+.It Sx \&%O Ta \&No Ta \&No Ta >0
+.It Sx \&%P Ta \&No Ta \&No Ta >0
+.It Sx \&%Q Ta \&No Ta \&No Ta >0
+.It Sx \&%R Ta \&No Ta \&No Ta >0
+.It Sx \&%T Ta \&No Ta \&No Ta >0
+.It Sx \&%U Ta \&No Ta \&No Ta >0
+.It Sx \&%V Ta \&No Ta \&No Ta >0
+.It Sx \&Ad Ta Yes Ta Yes Ta >0
+.It Sx \&An Ta Yes Ta Yes Ta >0
+.It Sx \&Ap Ta Yes Ta Yes Ta 0
+.It Sx \&Ar Ta Yes Ta Yes Ta n
+.It Sx \&At Ta Yes Ta Yes Ta 1
+.It Sx \&Bsx Ta Yes Ta Yes Ta n
+.It Sx \&Bt Ta \&No Ta \&No Ta 0
+.It Sx \&Bx Ta Yes Ta Yes Ta n
+.It Sx \&Cd Ta Yes Ta Yes Ta >0
+.It Sx \&Cm Ta Yes Ta Yes Ta >0
+.It Sx \&Db Ta \&No Ta \&No Ta 1
+.It Sx \&Dd Ta \&No Ta \&No Ta n
+.It Sx \&Dt Ta \&No Ta \&No Ta n
+.It Sx \&Dv Ta Yes Ta Yes Ta >0
+.It Sx \&Dx Ta Yes Ta Yes Ta n
+.It Sx \&Em Ta Yes Ta Yes Ta >0
+.It Sx \&Er Ta Yes Ta Yes Ta >0
+.It Sx \&Es Ta Yes Ta Yes Ta 2
+.It Sx \&Ev Ta Yes Ta Yes Ta >0
+.It Sx \&Ex Ta \&No Ta \&No Ta n
+.It Sx \&Fa Ta Yes Ta Yes Ta >0
+.It Sx \&Fd Ta \&No Ta \&No Ta >0
+.It Sx \&Fl Ta Yes Ta Yes Ta n
+.It Sx \&Fn Ta Yes Ta Yes Ta >0
+.It Sx \&Fr Ta Yes Ta Yes Ta >0
+.It Sx \&Ft Ta Yes Ta Yes Ta >0
+.It Sx \&Fx Ta Yes Ta Yes Ta n
+.It Sx \&Hf Ta \&No Ta \&No Ta n
+.It Sx \&Ic Ta Yes Ta Yes Ta >0
+.It Sx \&In Ta \&No Ta \&No Ta 1
+.It Sx \&Lb Ta \&No Ta \&No Ta 1
+.It Sx \&Li Ta Yes Ta Yes Ta >0
+.It Sx \&Lk Ta Yes Ta Yes Ta >0
+.It Sx \&Lp Ta \&No Ta \&No Ta 0
+.It Sx \&Ms Ta Yes Ta Yes Ta >0
+.It Sx \&Mt Ta Yes Ta Yes Ta >0
+.It Sx \&Nm Ta Yes Ta Yes Ta n
+.It Sx \&No Ta Yes Ta Yes Ta 0
+.It Sx \&Ns Ta Yes Ta Yes Ta 0
+.It Sx \&Nx Ta Yes Ta Yes Ta n
+.It Sx \&Os Ta \&No Ta \&No Ta n
+.It Sx \&Ot Ta Yes Ta Yes Ta >0
+.It Sx \&Ox Ta Yes Ta Yes Ta n
+.It Sx \&Pa Ta Yes Ta Yes Ta n
+.It Sx \&Pf Ta Yes Ta Yes Ta 1
+.It Sx \&Pp Ta \&No Ta \&No Ta 0
+.It Sx \&Rv Ta \&No Ta \&No Ta n
+.It Sx \&Sm Ta \&No Ta \&No Ta <2
+.It Sx \&St Ta \&No Ta Yes Ta 1
+.It Sx \&Sx Ta Yes Ta Yes Ta >0
+.It Sx \&Sy Ta Yes Ta Yes Ta >0
+.It Sx \&Tn Ta Yes Ta Yes Ta >0
+.It Sx \&Ud Ta \&No Ta \&No Ta 0
+.It Sx \&Ux Ta Yes Ta Yes Ta n
+.It Sx \&Va Ta Yes Ta Yes Ta n
+.It Sx \&Vt Ta Yes Ta Yes Ta >0
+.It Sx \&Xr Ta Yes Ta Yes Ta 2
+.El
+.Ss Delimiters
+When a macro argument consists of one single input character
+considered as a delimiter, the argument gets special handling.
+This does not apply when delimiters appear in arguments containing
+more than one character.
+Consequently, to prevent special handling and just handle it
+like any other argument, a delimiter can be escaped by prepending
+a zero-width space
+.Pq Sq \e& .
+In text lines, delimiters never need escaping, but may be used
+as normal punctuation.
+.Pp
+For many macros, when the leading arguments are opening delimiters,
+these delimiters are put before the macro scope,
+and when the trailing arguments are closing delimiters,
+these delimiters are put after the macro scope.
+Spacing is suppressed after opening delimiters
+and before closing delimiters.
+For example,
+.Pp
+.D1 Pf \. \&Aq "( [ word ] ) ."
+.Pp
+renders as:
+.Pp
+.D1 Aq ( [ word ] ) .
+.Pp
+Opening delimiters are:
+.Pp
+.Bl -tag -width Ds -offset indent -compact
+.It \&(
+left parenthesis
+.It \&[
+left bracket
+.El
+.Pp
+Closing delimiters are:
+.Pp
+.Bl -tag -width Ds -offset indent -compact
+.It \&.
+period
+.It \&,
+comma
+.It \&:
+colon
+.It \&;
+semicolon
+.It \&)
+right parenthesis
+.It \&]
+right bracket
+.It \&?
+question mark
+.It \&!
+exclamation mark
+.El
+.Pp
+Note that even a period preceded by a backslash
+.Pq Sq \e.\&
+gets this special handling; use
+.Sq \e&.
+to prevent that.
+.Pp
+Many in-line macros interrupt their scope when they encounter
+delimiters, and resume their scope when more arguments follow that
+are not delimiters.
+For example,
+.Pp
+.D1 Pf \. \&Fl "a ( b | c \e*(Ba d ) e"
+.Pp
+renders as:
+.Pp
+.D1 Fl a ( b | c \*(Ba d ) e
+.Pp
+This applies to both opening and closing delimiters,
+and also to the middle delimiter, which does not suppress spacing:
+.Pp
+.Bl -tag -width Ds -offset indent -compact
+.It \&|
+vertical bar
+.El
+.Pp
+As a special case, the predefined string \e*(Ba is handled and rendered
+in the same way as a plain
+.Sq \&|
+character.
+Using this predefined string is not recommended in new manuals.
+.Ss Font handling
+In
+.Nm
+documents, usage of semantic markup is recommended in order to have
+proper fonts automatically selected; only when no fitting semantic markup
+is available, consider falling back to
+.Sx Physical markup
+macros.
+Whenever any
+.Nm
+macro switches the
+.Xr roff 7
+font mode, it will automatically restore the previous font when exiting
+its scope.
+Manually switching the font using the
+.Xr roff 7
+.Ql \ef
+font escape sequences is never required.
+.Sh COMPATIBILITY
+This section provides an incomplete list of compatibility issues
+between mandoc and GNU troff
+.Pq Qq groff .
+.Pp
+The following problematic behaviour is found in groff:
+.Pp
+.Bl -dash -compact
+.It
+.Sx \&Dd
+with non-standard arguments behaves very strangely.
+When there are three arguments, they are printed verbatim.
+Any other number of arguments is replaced by the current date,
+but without any arguments the string
+.Dq Epoch
+is printed.
+.It
+.Sx \&Lk
+only accepts a single link-name argument; the remainder is misformatted.
+.It
+.Sx \&Pa
+does not format its arguments when used in the FILES section under
+certain list types.
+.It
+.Sx \&Ta
+can only be called by other macros, but not at the beginning of a line.
+.It
+.Sx \&%C
+is not implemented (up to and including groff-1.22.2).
+.It
+.Sq \ef
+.Pq font face
+and
+.Sq \eF
+.Pq font family face
+.Sx Text Decoration
+escapes behave irregularly when specified within line-macro scopes.
+.It
+Negative scaling units return to prior lines.
+Instead, mandoc truncates them to zero.
+.El
+.Pp
+The following features are unimplemented in mandoc:
+.Pp
+.Bl -dash -compact
+.It
+.Sx \&Bd
+.Fl file Ar file
+is unsupported for security reasons.
+.It
+.Sx \&Bd
+.Fl filled
+does not adjust the right margin, but is an alias for
+.Sx \&Bd
+.Fl ragged .
+.It
+.Sx \&Bd
+.Fl literal
+does not use a literal font, but is an alias for
+.Sx \&Bd
+.Fl unfilled .
+.It
+.Sx \&Bd
+.Fl offset Cm center
+and
+.Fl offset Cm right
+don't work.
+Groff does not implement centered and flush-right rendering either,
+but produces large indentations.
+.El
+.Sh SEE ALSO
+.Xr man 1 ,
+.Xr mandoc 1 ,
+.Xr eqn 7 ,
+.Xr man 7 ,
+.Xr mandoc_char 7 ,
+.Xr roff 7 ,
+.Xr tbl 7
+.Pp
+The web page
+.Lk http://mandoc.bsd.lv/mdoc/ "extended documentation for the mdoc language"
+provides a few tutorial-style pages for beginners, an extensive style
+guide for advanced authors, and an alphabetic index helping to choose
+the best macros for various kinds of content.
+.Sh HISTORY
+The
+.Nm
+language first appeared as a troff macro package in
+.Bx 4.4 .
+It was later significantly updated by Werner Lemberg and Ruslan Ermilov
+in groff-1.17.
+The standalone implementation that is part of the
+.Xr mandoc 1
+utility written by Kristaps Dzonsons appeared in
+.Ox 4.6 .
+.Sh AUTHORS
+The
+.Nm
+reference was written by
+.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
git.ckatri.com / mandoc.git / blobdiff