Provided by: mandoc_1.14.3-3_amd64 
NAME
mandoc - format manual pages
SYNOPSIS
mandoc [-ac] [-I os=name] [-K encoding] [-mdoc | -man] [-O options] [-T output] [-W level] [file ...]
DESCRIPTION
The mandoc utility formats UNIX manual pages for display.
By default, mandoc reads mdoc(7) or man(7) text from stdin and produces -T locale output.
The options are as follows:
-a If the standard output is a terminal device and -c is not specified, use more(1) to paginate the
output, just like man(1) would.
-c Copy the formatted manual pages to the standard output without using more(1) to paginate them.
This is the default. It can be specified to override -a.
-I os=name
Override the default operating system name for the mdoc(7) Os and for the man(7) TH macro.
-K encoding
Specify the input encoding. The supported encoding arguments are us-ascii, iso-8859-1, and
utf-8. If not specified, autodetection uses the first match in the following list:
1. If the first three bytes of the input file are the UTF-8 byte order mark (BOM, 0xefbbbf),
input is interpreted as utf-8.
2. If the first or second line of the input file matches the emacs mode line format
.\" -*- [...;] coding: encoding; -*-
then input is interpreted according to encoding.
3. If the first non-ASCII byte in the file introduces a valid UTF-8 sequence, input is
interpreted as utf-8.
4. Otherwise, input is interpreted as iso-8859-1.
-mdoc | -man
With -mdoc, all input files are interpreted as mdoc(7). With -man, all input files are
interpreted as man(7). By default, the input language is automatically detected for each file:
if the the first macro is Dd or Dt, the mdoc(7) parser is used; otherwise, the man(7) parser is
used. With other arguments, -m is silently ignored.
-O options
Comma-separated output options.
-T output
Output format. See Output Formats for available formats. Defaults to -T locale.
-W level
Specify the minimum message level to be reported on the standard error output and to affect the
exit status. The level can be base, style, warning, error, or unsupp. The base level
automatically derives the operating system from the contents of the Os macro, from the -Ios
command line option, or from the uname(3) return value. The levels openbsd and netbsd are
variants of base that bypass autodetection and request validation of base system conventions for
a particular operating system. The level all is an alias for base. By default, mandoc is
silent. See EXIT STATUS and DIAGNOSTICS for details.
The special option -W stop tells mandoc to exit after parsing a file that causes warnings or
errors of at least the requested level. No formatted output will be produced from that file. If
both a level and stop are requested, they can be joined with a comma, for example -W error,stop.
file Read input from zero or more files. If unspecified, reads from stdin. If multiple files are
specified, mandoc will halt with the first failed parse.
The options -fhklw are also supported and are documented in man(1). In -f and -k mode, mandoc also
supports the options -CMmOSs described in the apropos(1) manual. The options -fkl are mutually exclusive
and override each other.
Output Formats
The mandoc utility accepts the following -T arguments, which correspond to output modes:
-T ascii Produce 7-bit ASCII output. See ASCII Output.
-T html Produce HTML5, CSS1, and MathML output. See HTML Output.
-T lint Parse only: produce no output. Implies -W all and redirects parser messages, which usually
appear on standard error output, to standard output.
-T locale Encode output using the current locale. This is the default. See Locale Output.
-T man Produce man(7) format output. See Man Output.
-T markdown
Produce output in markdown format. See Markdown Output.
-T pdf Produce PDF output. See PDF Output.
-T ps Produce PostScript output. See PostScript Output.
-T tree Produce an indented parse tree. See Syntax tree output.
-T utf8 Encode output in the UTF-8 multi-byte format. See UTF-8 Output.
If multiple input files are specified, these will be processed by the corresponding filter in-order.
ASCII Output
Output produced by -T ascii is rendered in standard 7-bit ASCII documented in ascii(7).
Font styles are applied by using back-spaced encoding such that an underlined character ‘c’ is rendered
as ‘_\[bs]c’, where ‘\[bs]’ is the back-space character number 8. Emboldened characters are rendered as
‘c\[bs]c’.
The special characters documented in mandoc_char(7) are rendered best-effort in an ASCII equivalent.
Output width is limited to 78 visible columns unless literal input lines exceed this limit.
The following -O arguments are accepted:
indent=indent
The left margin for normal text is set to indent blank characters instead of the default of five
for mdoc(7) and seven for man(7). Increasing this is not recommended; it may result in degraded
formatting, for example overfull lines or ugly line breaks.
width=width
The output width is set to width.
HTML Output
Output produced by -T html conforms to HTML5 using optional self-closing tags. Default styles use only
CSS1. Equations rendered from eqn(7) blocks use MathML.
The mandoc.css file documents style-sheet classes available for customising output. If a style-sheet is
not specified with -O style, -T html defaults to simple output (via an embedded style-sheet) readable in
any graphical or text-based web browser.
Special characters are rendered in decimal-encoded UTF-8.
The following -O arguments are accepted:
fragment
Omit the <!DOCTYPE> declaration and the <html>, <head>, and <body> elements and only emit the
subtree below the <body> element. The style argument will be ignored. This is useful when
embedding manual content within existing documents.
includes=fmt
The string fmt, for example, ../src/%I.html, is used as a template for linked header files
(usually via the In macro). Instances of ‘%I’ are replaced with the include filename. The
default is not to present a hyperlink.
man=fmt
The string fmt, for example, ../html%S/%N.%S.html, is used as a template for linked manuals
(usually via the Xr macro). Instances of ‘%N’ and ‘%S’ are replaced with the linked manual's
name and section, respectively. If no section is included, section 1 is assumed. The default is
not to present a hyperlink.
style=style.css
The file style.css is used for an external style-sheet. This must be a valid absolute or
relative URI.
Locale Output
Locale-depending output encoding is triggered with -T locale. This is the default.
This option is not available on all systems: systems without locale support, or those whose internal
representation is not natively UCS-4, will fall back to -T ascii. See ASCII Output for font style
specification and available command-line arguments.
Man Output
Translate input format into man(7) output format. This is useful for distributing manual sources to
legacy systems lacking mdoc(7) formatters.
If mdoc(7) is passed as input, it is translated into man(7). If the input format is man(7), the input is
copied to the output, expanding any roff(7) so requests. The parser is also run, and as usual, the -W
level controls which DIAGNOSTICS are displayed before copying the input to the output.
Markdown Output
Translate mdoc(7) input to the markdown format conforming to John Gruber's 2004 specification:
http://daringfireball.net/projects/markdown/syntax.text.
The output also almost conforms to the CommonMark: http://commonmark.org/ specification.
The character set used for the markdown output is ASCII. Non-ASCII characters are encoded as HTML
entities. Since that is not possible in literal font contexts, because these are rendered as code spans
and code blocks in the markdown output, non-ASCII characters are transliterated to ASCII approximations
in these contexts.
Markdown is a very weak markup language, so all semantic markup is lost, and even part of the
presentational markup may be lost. Do not use this as an intermediate step in converting to HTML;
instead, use -T html directly.
The man(7), tbl(7), and eqn(7) input languages are not supported by -T markdown output mode.
PDF Output
PDF-1.1 output may be generated by -T pdf. See PostScript Output for -O arguments and defaults.
PostScript Output
PostScript "Adobe-3.0" Level-2 pages may be generated by -T ps. Output pages default to letter sized and
are rendered in the Times font family, 11-point. Margins are calculated as 1/9 the page length and
width. Line-height is 1.4m.
Special characters are rendered as in ASCII Output.
The following -O arguments are accepted:
paper=name
The paper size name may be one of a3, a4, a5, legal, or letter. You may also manually specify
dimensions as NNxNN, width by height in millimetres. If an unknown value is encountered, letter
is used.
UTF-8 Output
Use -T utf8 to force a UTF-8 locale. See Locale Output for details and options.
Syntax tree output
Use -T tree to show a human readable representation of the syntax tree. It is useful for debugging the
source code of manual pages. The exact format is subject to change, so don't write parsers for it.
The first paragraph shows meta data found in the mdoc(7) prologue, on the man(7) TH line, or the
fallbacks used.
In the tree dump, each output line shows one syntax tree node. Child nodes are indented with respect to
their parent node. The columns are:
1. For macro nodes, the macro name; for text and tbl(7) nodes, the content. There is a special format
for eqn(7) nodes.
2. Node type (text, elem, block, head, body, body-end, tail, tbl, eqn).
3. Flags:
- An opening parenthesis if the node is an opening delimiter.
- An asterisk if the node starts a new input line.
- The input line number (starting at one).
- A colon.
- The input column number (starting at one).
- A closing parenthesis if the node is a closing delimiter.
- A full stop if the node ends a sentence.
- BROKEN if the node is a block broken by another block.
- NOSRC if the node is not in the input file, but automatically generated from macros.
- NOPRT if the node is not supposed to generate output for any output format.
The following -O argument is accepted:
noval Skip validation and show the unvalidated syntax tree. This can help to find out whether a given
behaviour is caused by the parser or by the validator. Meta data is not available in this case.
ENVIRONMENT
MANPAGER Any non-empty value of the environment variable MANPAGER is used instead of the standard
pagination program, more(1); see man(1) for details. Only used if -a or -l is specified.
PAGER Specifies the pagination program to use when MANPAGER is not defined. If neither PAGER nor
MANPAGER is defined, more(1) -s is used. Only used if -a or -l is specified.
EXIT STATUS
The mandoc utility exits with one of the following values, controlled by the message level associated
with the -W option:
0 No base system convention violations, style suggestions, warnings, or errors occurred, or those
that did were ignored because they were lower than the requested level.
1 At least one base system convention violation or style suggestion occurred, but no warning or
error, and -W base or -W style was specified.
2 At least one warning occurred, but no error, and -W warning or a lower level was requested.
3 At least one parsing error occurred, but no unsupported feature was encountered, and -W error or
a lower level was requested.
4 At least one unsupported feature was encountered, and -W unsupp or a lower level was requested.
5 Invalid command line arguments were specified. No input files have been read.
6 An operating system error occurred, for example exhaustion of memory, file descriptors, or
process table entries. Such errors cause mandoc to exit at once, possibly in the middle of
parsing or formatting a file.
Note that selecting -T lint output mode implies -W all.
EXAMPLES
To page manuals to the terminal:
$ mandoc -l mandoc.1 man.1 apropos.1 makewhatis.8
To produce HTML manuals with mandoc.css as the style-sheet:
$ mandoc -T html -O style=mandoc.css mdoc.7 > mdoc.7.html
To check over a large set of manuals:
$ mandoc -T lint `find /usr/src -name \*\.[1-9]`
To produce a series of PostScript manuals for A4 paper:
$ mandoc -T ps -O paper=a4 mdoc.7 man.7 > manuals.ps
Convert a modern mdoc(7) manual to the older man(7) format, for use on systems lacking an mdoc(7) parser:
$ mandoc -T man foo.mdoc > foo.man
DIAGNOSTICS
Messages displayed by mandoc follow this format:
mandoc: file:line:column: level: message: macro args (os)
Line and column numbers start at 1. Both are omitted for messages referring to an input file as a whole.
Macro names and arguments are omitted where meaningless. The os operating system specifier is omitted
for messages that are relevant for all operating systems. Fatal messages about invalid command line
arguments or operating system errors, for example when memory is exhausted, may also omit the file and
level fields.
Message levels have the following meanings:
unsupp An input file uses unsupported low-level roff(7) features. The output may be incomplete and/or
misformatted, so using GNU troff instead of mandoc to process the file may be preferable.
error Indicates a risk of information loss or severe misformatting, in most cases caused by serious
syntax errors.
warning Indicates a risk that the information shown or its formatting may mismatch the author's intent
in minor ways. Additionally, syntax errors are classified at least as warnings, even if they do
not usually cause misformatting.
style An input file uses dubious or discouraged style. This is not a complaint about the syntax, and
probably neither formatting nor portability are in danger. While great care is taken to avoid
false positives on the higher message levels, the style level tries to reduce the probability
that issues go unnoticed, so it may occasionally issue bogus suggestions. Please use your good
judgement to decide whether any particular style suggestion really justifies a change to the
input file.
base A convertion used in the base system of a specific operating system is not adhered to. These
are not markup mistakes, and neither the quality of formatting nor portability are in danger.
Messages of the base level are printed with the more intuitive style level tag.
Messages of the base, style, warning, error, and unsupp levels except those about non-existent or
unreadable input files are hidden unless their level, or a lower level, is requested using a -W option or
-T lint output mode.
As indicated below, all base and some style checks are only performed if a specific operating system name
occurs in the arguments of the -W command line option, of the Os macro, of the -Ios command line option,
or, if neither are present, in the return value of the uname(3) function.
Conventions for base system manuals
®.br (mdoc, NetBSD) The Dd macro uses CVS Mdocdate keyword substitution, which is not supported by the
NetBSD base system. Consider using the conventional Month dd, yyyy format instead.
®.br (mdoc, OpenBSD) The Dd macro does not use CVS Mdocdate keyword substitution, but using it is
conventionally expected in the OpenBSD base system.
®.br (mdoc, OpenBSD, NetBSD) The third argument of the Dt macro does not match any of the architectures
this operating system is running on.
®.br (mdoc, OpenBSD, NetBSD) The Os macro has an argument. In the base system, it is conventionally left
blank.
®.br (OpenBSD, NetBSD) The manual page lacks the comment line with the RCS identifier generated by CVS
OpenBSD or NetBSD keyword substitution as conventionally used in these operating systems.
®.br (mdoc) An Xr macro references a manual page that is not found in the base system. The path to look
for base system manuals is configurable at compile time and defaults to /usr/share/man: /usr/X11R6/man.
Style suggestions
®.br (mdoc) The Dd macro uses the legacy man(7) date format yyyy-dd-mm. Consider using the conventional
mdoc(7) date format Month dd, yyyy instead.
®.br (mdoc, man) The title is still used as given in the Dt or TH macro.
®.br A single manual page contains two copies of the RCS identifier for the same operating system.
Consider deleting the later instance and moving the first one up to the top of the page.
®.br (mdoc) Fuzzy string matching revealed that the argument of an Sh macro is similar, but not identical
to a standard section name.
®.br (roff) Macro arguments can be enclosed in double quote characters such that space characters and
macro names contained in the quoted argument need not be escaped. The closing quote of the last argument
of a macro can be omitted. However, omitting it is not recommended because it makes the code harder to
read.
®.br (mdoc) A Bt, Tn, or Ud macro was found. Simply delete it: it serves no useful purpose.
®.br (mdoc) A string was found in plain text or in a Bx macro that could be represented using Ox, Nx, Fx,
or Dx.
®.br (mdoc, NetBSD) The Er items in a Bl list are not in alphabetical order.
®.br (mdoc, NetBSD) A Bl list contains two consecutive It entries describing the same Er number.
®.br (mdoc) The last argument of an Ex, Fo, Nd, Nm, Os, Sh, Ss, St, or Sx macro ends with a trailing
delimiter. This is usually bad style and often indicates typos. Most likely, the delimiter can be
removed.
®.br (mdoc) The last argument of a macro that supports trailing delimiter arguments is longer than one
byte and ends with a trailing delimiter. Consider inserting a blank such that the delimiter becomes a
separate argument, thus moving it out of the scope of the macro.
®.br (man) A fi request occurs even though the document is still in fill mode, or already switched back
to fill mode. It has no effect.
®.br (man) An nf request occurs even though the document already switched to no-fill mode and did not
switch back to fill mode yet. It has no effect.
®.br (mdoc) A word followed by an empty pair of parentheses occurs on a text line. Consider using an Fn
or Xr macro.
®.br (mdoc, man, roff) Whitespace at the end of input lines is almost never semantically significant —
but in the odd case where it might be, it is extremely confusing when reviewing and maintaining
documents.
®.br (roff) Comment lines start with a dot, a backslash, and a double-quote character. The mandoc
utility treats the line as a comment line even without the backslash, but leaving out the backslash might
not be portable.
Warnings related to the document prologue
®.br (mdoc) A Dt macro has no arguments, or there is no Dt macro before the first non-prologue macro.
®.br (man) There is no TH macro, or it has no arguments.
®.br (mdoc, man) A Dt or TH macro lacks the mandatory section argument.
®.br (mdoc) The section number in a Dt line is invalid, but still used.
®.br (mdoc, man) The document was parsed as mdoc(7) and it has no Dd macro, or the Dd macro has no
arguments or only empty arguments; or the document was parsed as man(7) and it has no TH macro, or the TH
macro has less than three arguments or its third argument is empty.
®.br (mdoc, man) The date given in a Dd or TH macro does not follow the conventional format.
®.br (mdoc, man) The date given in a Dd or TH macro is more than a day ahead of the current system
time(3).
®.br (mdoc) The default or current system is not shown in this case.
®.br (mdoc) A Dd or Os macro occurs after some non-prologue macro, but still takes effect.
®.br (mdoc) The prologue macros are not given in the conventional order Dd, Dt, Os. All three macros are
used even when given in another order.
Warnings regarding document structure
®.br (roff) Including files only works when the parser program runs with the correct current working
directory.
®.br (mdoc, man) The document body contains neither text nor macros. An empty document is shown,
consisting only of a header and a footer line.
®.br (mdoc, man) Some macros or text precede the first Sh or SH section header. The offending macros and
text are parsed and added to the top level of the syntax tree, outside any section block.
®.br (mdoc) The argument of the first Sh macro is not ‘NAME’. This may confuse makewhatis(8) and
apropos(1).
®.br (mdoc) The NAME section does not contain any Nm child macro before the first Nd macro.
®.br (mdoc) The NAME section lacks the mandatory Nd child macro.
®.br (mdoc) The NAME section does contain an Nd child macro, but other content follows it.
®.br (mdoc) The NAME section contains plain text or macros other than Nm and Nd.
®.br (mdoc) The NAME section contains an Nm macro that is neither the first one nor preceded by a comma.
®.br (mdoc) The Nd macro lacks the required argument. The title line of the manual will end after the
dash.
®.br (mdoc) An Nd macro appears outside the NAME section. The arguments are printed anyway and the
following text is used for apropos(1), but none of that behaviour is portable.
®.br (mdoc) A standard section occurs after another section it usually precedes. All section titles are
used as given, and the order of sections is not changed.
®.br (mdoc) The same standard section title occurs more than once.
®.br (mdoc) A standard section header occurs in a section of the manual where it normally isn't useful.
®.br (mdoc) An Xr macro refers to a name and section matching the section of the present manual page and
a name mentioned in an Nm macro in the NAME or SYNOPSIS section, or in an Fn or Fo macro in the SYNOPSIS.
Consider using Nm or Fn instead of Xr.
®.br (mdoc) In the SEE ALSO section, an Xr macro with a lower section number follows one with a higher
number, or two Xr macros referring to the same section are out of alphabetical order.
®.br (mdoc) In the SEE ALSO section, punctuation between two Xr macros differs from a single comma, or
there is trailing punctuation after the last Xr macro.
®.br (mdoc) An AUTHORS sections contains no An macros, or only empty ones. Probably, there are author
names lacking markup.
Warnings related to macros and nesting
®.br (mdoc) See the mdoc(7) manual for replacements.
®.br (mdoc) The name of a macro that is not callable appears on a macro line. It is printed verbatim.
If the intention is to call it, move it to its own input line; otherwise, escape it by prepending ‘\&’.
®.br In mdoc(7) documents, this happens
- at the beginning and end of sections and subsections
- right before non-compact lists and displays
- at the end of items in non-column, non-compact lists
- and for multiple consecutive paragraph macros.
In man(7) documents, it happens
- for empty P, PP, and LP macros
- for IP macros having neither head nor body arguments
- for br or sp right after SH or SS
®.br (mdoc) A list item in a Bl list contains a trailing paragraph macro. The paragraph macro is moved
after the end of the list.
®.br (mdoc) An input line begins with an Ns macro, or the next argument after an Ns macro is an isolated
closing delimiter. The macro is ignored.
®.br (mdoc) If two blocks intersect, one should completely contain the other. Otherwise, rendered output
is likely to look strange in any output format, and rendering in SGML-based output formats is likely to
be outright wrong because such languages do not support badly nested blocks at all. Typical examples of
badly nested blocks are "Ao Bo Ac Bc" and "Ao Bq Ac". In these examples, Ac breaks Bo and Bq,
respectively.
®.br (mdoc) A Bd, D1, or Dl display occurs nested inside another Bd display. This works with mandoc, but
fails with most other implementations.
®.br (mdoc) A Bl list block contains text or macros before the first It macro. The offending children
are moved before the beginning of the list.
®.br Inside a Bl -column list, a Ta macro occurs as the first macro on a line, which is not portable.
®.br (man) While parsing the next-line scope of the previous macro, another macro is found that
prematurely terminates the previous one. The previous, interrupted macro is deleted from the parse tree.
Warnings related to missing arguments
®.br (roff, eqn) The macro name is missing from a macro definition request, or an eqn(7) control
statement or operation keyword lacks its required argument.
®.br (roff) A conditional request is only useful if any of the following follows it on the same logical
input line:
- The ‘\{’ keyword to open a multi-line scope.
- A request or macro or some text, resulting in a single-line scope.
- The immediate end of the logical line without any intervening whitespace, resulting in next-line
scope.
Here, a conditional request is followed by trailing whitespace only, and there is no other content on its
logical input line. Note that it doesn't matter whether the logical input line is split across multiple
physical input lines using ‘\’ line continuation characters. This is one of the rare cases where
trailing whitespace is syntactically significant. The conditional request controls a scope containing
whitespace only, so it is unlikely to have a significant effect, except that it may control a following
el clause.
®.br (mdoc) The indicated macro has no arguments and hence no effect.
®.br (mdoc, man) A Bd, Bk, Bl, D1, Dl, MT, RS, or UR block contains nothing in its body and will produce
no output.
®.br (mdoc) The required width is missing after Bd or Bl -offset or -width.
®.br (mdoc) The Bd macro is invoked without the required display type.
®.br (mdoc) In a Bl macro, at least one other argument precedes the type argument. The mandoc utility
copes with any argument order, but some other mdoc(7) implementations do not.
®.br (mdoc) Every Bl macro having the -tag argument requires -width, too.
®.br (mdoc) The Ex -std macro is called without an argument before Nm has first been called with an
argument.
®.br (mdoc) The Fo macro is called without an argument. No function name is printed.
®.br (mdoc) In a Bl -diag, -hang, -inset, -ohang, or -tag list, an It macro lacks the required argument.
The item head is left empty.
®.br (mdoc) In a Bl -bullet, -dash, -enum, or -hyphen list, an It block is empty. An empty list item is
shown.
®.br (mdoc) An It macro in a Bd -column list has no arguments. While mandoc uses the text or macros of
the following line, if any, for the cell, other formatters may misformat the list.
®.br (mdoc) A Bf macro has no argument. It switches to the default font.
®.br (mdoc) The Bf argument is invalid. The default font is used instead.
®.br (mdoc) A Pf macro has no argument, or only one argument and no macro follows on the same input line.
This defeats its purpose; in particular, spacing is not suppressed before the text or macros following on
the next input line.
®.br (mdoc) An Rs macro is immediately followed by an Re macro on the next input line. Such an empty
block does not produce any output.
®.br (mdoc) An Xr macro lacks its second, section number argument. The first argument, i.e. the name, is
printed, but without subsequent parentheses.
®.br (mdoc) An Ex or Rv macro lacks the required -std argument. The mandoc utility assumes -std even
when it is not specified, but other implementations may not.
®.br (man) The OP macro is invoked without any argument. An empty pair of square brackets is shown.
®.br (man) The MT or UR macro is invoked without any argument. An empty pair of angle brackets is shown.
®.br (eqn) A diacritic mark or a binary operator is found, but there is nothing to the left of it. An
empty box is inserted.
Warnings related to bad macro arguments
®.br (mdoc) A Bd or Bl macro has more than one -compact, more than one -offset, or more than one -width
argument. All but the last instances of these arguments are ignored.
®.br (mdoc) An An macro has more than one -split or -nosplit argument. All but the first of these
arguments are ignored.
®.br (mdoc) A Bd macro has more than one type argument; the first one is used.
®.br (mdoc) A Bl macro has more than one type argument; the first one is used.
®.br (mdoc) A Bl -column, -diag, -ohang, -inset, or -item list has a -width argument. That has no
effect.
®.br In a line of a Bl -column list, the number of tabs or Ta macros is less than the number expected
from the list header line or exceeds the expected number by more than one. Missing cells remain empty,
and all cells exceeding the number of columns are joined into one single cell.
®.br (mdoc) An At macro has an invalid argument. It is used verbatim, with "AT&T UNIX " prefixed to it.
®.br (mdoc) An argument of an Fa or Fn macro contains a comma; it should probably be split into two
arguments.
®.br (mdoc) The first argument of an Fc or Fn macro contains an opening or closing parenthesis; that's
probably wrong, parentheses are added automatically.
®.br (mdoc, not on OpenBSD) An Lb macro has an unknown name argument and will be rendered as "library
name".
®.br (mdoc) An Rs block contains plain text or non-% macros. The bogus content is left in the syntax
tree. Formatting may be poor.
®.br (mdoc) An Sm macro has an argument other than on or off. The invalid argument is moved out of the
macro, which leaves the macro empty, causing it to toggle the spacing mode.
®.br (man, tbl) A roff(7) ft request or a tbl(7) f layout modifier has an unknown font argument.
®.br (roff) A tr request contains an odd number of characters. The last character is mapped to the blank
character.
Warnings related to plain text
®.br (mdoc) The meaning of blank input lines is only well-defined in non-fill mode: In fill mode, line
breaks of text input lines are not supposed to be significant. However, for compatibility with groff,
blank lines in fill mode are replaced with sp requests.
®.br (mdoc, man) The meaning of tab characters is only well-defined in non-fill mode: In fill mode,
whitespace is not supposed to be significant on text input lines. As an implementation dependent choice,
tab characters on text lines are passed through to the formatters in any case. Given that the text
before the tab character will be filled, it is hard to predict which tab stop position the tab will
advance to.
®.br (mdoc) A new sentence starts in the middle of a text line. Start it on a new input line to help
formatters produce correct spacing.
®.br (roff) An escape sequence has an invalid opening argument delimiter, lacks the closing argument
delimiter, or the argument has too few characters. If the argument is incomplete, \* and \n expand to an
empty string, \B to the digit ‘0’, and \w to the length of the incomplete argument. All other invalid
escape sequences are ignored.
®.br (roff) If a string is used without being defined before, its value is implicitly set to the empty
string. However, defining strings explicitly before use keeps the code more readable.
Warnings related to tables
®.br (tbl) The first cell in a table layout line is a horizontal span (‘s’). Data provided for this cell
is ignored, and nothing is printed in the cell.
®.br (tbl) The first line of a table layout specification requests a vertical span (‘^’). Data provided
for this cell is ignored, and nothing is printed in the cell.
®.br (tbl) A table layout specification contains more than two consecutive vertical bars. A double bar
is printed, all additional bars are discarded.
Errors related to tables
®.br (tbl) The table options line contains a character other than a letter, blank, or comma where the
beginning of an option name is expected. The character is ignored.
®.br (tbl) The table options line contains a string of letters that does not match any known option name.
The word is ignored.
®.br (tbl) A table option that requires an argument is not followed by an opening parenthesis, or the
opening parenthesis is immediately followed by a closing parenthesis. The option is ignored.
®.br (tbl) A table option argument contains an invalid number of characters. Both the option and the
argument are ignored.
®.br (tbl) A table layout specification is completely empty, specifying zero lines and zero columns. As
a fallback, a single left-justified column is used.
®.br (tbl) A table layout specification contains a character that can neither be interpreted as a layout
key character nor as a layout modifier, or a modifier precedes the first key. The invalid character is
discarded.
®.br (tbl) A table layout specification contains an opening parenthesis, but no matching closing
parenthesis. The rest of the input line, starting from the parenthesis, has no effect.
®.br (tbl) A table does not contain any data cells. It will probably produce no output.
®.br (tbl) A table cell is marked as a horizontal span (‘s’) or vertical span (‘^’) in the table layout,
but it contains data. The data is ignored.
®.br (tbl) A data line contains more cells than the corresponding layout line. The data in the extra
cells is ignored.
®.br (tbl) A data block is opened with T{, but never closed with a matching T}. The remaining data lines
of the table are all put into one cell, and any remaining cells stay empty.
Errors related to roff, mdoc, and man code
®.br (mdoc) One of the prologue macros occurs more than once. The last instance overrides all previous
ones.
®.br (mdoc) The Dt macro appears after the first non-prologue macro. Traditional formatters cannot
handle this because they write the page header before parsing the document body. Even though this
technical restriction does not apply to mandoc, traditional semantics is preserved. The late macro is
discarded including its arguments.
®.br (roff) Explicit recursion limits are implemented for the following features, in order to prevent
infinite loops:
- expansion of nested escape sequences including expansion of strings and number registers,
- expansion of nested user-defined macros,
- and so file inclusion.
When a limit is hit, the output is incorrect, typically losing some content, but the parser can continue.
®.br (mdoc, man, roff) The input file contains a byte that is not a printable ascii(7) character. The
message mentions the character number. The offending byte is replaced with a question mark (‘?’).
Consider editing the input file to replace the byte with an ASCII transliteration of the intended
character.
®.br (mdoc, man, roff) The first identifier on a request or macro line is neither recognized as a roff(7)
request, nor as a user-defined macro, nor, respectively, as an mdoc(7) or man(7) macro. It may be
mistyped or unsupported. The request or macro is discarded including its arguments.
®.br (roff) An input file attempted to run a shell command or to read or write an external file. Such
attempts are denied for security reasons.
®.br (mdoc, eqn) An It macro occurs outside any Bl list, or an eqn(7) above delimiter occurs outside any
pile. It is discarded including its arguments.
®.br (mdoc) A Ta macro occurs outside any Bl -column block. It is discarded including its arguments.
®.br (mdoc, man, eqn, tbl, roff) Various syntax elements can only be used to explicitly close blocks that
have previously been opened. An mdoc(7) block closing macro, a man(7) ME, RE or UE macro, an eqn(7)
right delimiter or closing brace, or the end of an equation, table, or roff(7) conditional request is
encountered but no matching block is open. The offending request or macro is discarded.
®.br (man) The RE macro is invoked with an argument, but less than the specified number of RS blocks is
open. The RE macro is discarded.
®.br (mdoc, tbl) Various mdoc(7) macros as well as tables require explicit closing by dedicated macros.
A block that doesn't support bad nesting ends before all of its children are properly closed. The open
child nodes are closed implicitly.
®.br (mdoc, man, eqn, tbl, roff) At the end of the document, an explicit mdoc(7) block, a man(7) next-
line scope or MT, RS or UR block, an equation, table, or roff(7) conditional or ignore block is still
open. The open block is closed implicitly.
®.br (roff) Macro, string and register identifiers consist of printable, non-whitespace ASCII characters.
Escape sequences and characters and strings expressed in terms of them cannot form part of a name. The
first argument of an am, as, de, ds, nr, or rr request, or any argument of an rm request, or the name of
a request or user defined macro being called, is terminated by an escape sequence. In the cases of as,
ds, and nr, the request has no effect at all. In the cases of am, de, rr, and rm, what was parsed up to
this point is used as the arguments to the request, and the rest of the input line is discarded including
the escape sequence. When parsing for a request or a user-defined macro name to be called, only the
escape sequence is discarded. The characters preceding it are used as the request or macro name, the
characters following it are used as the arguments to the request or macro.
®.br (mdoc) For security reasons, the Bd macro does not support the -file argument. By requesting the
inclusion of a sensitive file, a malicious document might otherwise trick a privileged user into
inadvertently displaying the file on the screen, revealing the file content to bystanders. The argument
is ignored including the file name following it.
®.br (mdoc) A Bd block macro does not have any arguments. The block is discarded, and the block content
is displayed in whatever mode was active before the block.
®.br (mdoc) A Bl macro fails to specify the list type.
®.br (roff) The argument of a ce request is not a number.
®.br (mdoc) The first call to Nm, or any call in the NAME section, lacks the required argument.
®.br (mdoc) The Os macro is called without arguments, and the uname(3) system call failed. As a
workaround, mandoc can be compiled with -DOSNAME="\"string\"".
®.br (mdoc) An St macro has an unknown argument and is discarded.
®.br (roff, eqn) An it request or an eqn(7) size or gsize statement has a non-numeric or negative
argument or no argument at all. The invalid request or statement is ignored.
®.br (roff) For security reasons, mandoc allows so file inclusion requests only with relative paths and
only without ascending to any parent directory. By requesting the inclusion of a sensitive file, a
malicious document might otherwise trick a privileged user into inadvertently displaying the file on the
screen, revealing the file content to bystanders. mandoc only shows the path as it appears behind so.
®.br (roff) Servicing a so request requires reading an external file, but the file could not be opened.
mandoc only shows the path as it appears behind so.
®.br (mdoc, man, eqn, roff) An mdoc(7) Bt, Ed, Ef, Ek, El, Lp, Pp, Re, Rs, or Ud macro, an It macro in a
list that don't support item heads, a man(7) LP, P, or PP macro, an eqn(7) EQ or EN macro, or a roff(7)
br, fi, or nf request or ‘..’ block closing request is invoked with at least one argument. All
arguments are ignored.
®.br (mdoc, man, roff) A macro or request is invoked with too many arguments:
- Fo, MT, PD, RS, UR, ft, or sp with more than one argument
- An with another argument after -split or -nosplit
- RE with more than one argument or with a non-integer argument
- OP or a request of the de family with more than two arguments
- Dt with more than three arguments
- TH with more than five arguments
- Bd, Bk, or Bl with invalid arguments
The excess arguments are ignored.
Unsupported features
®.br (mdoc, man) Currently, mandoc cannot handle input files larger than its arbitrary size limit of 2^31
bytes (2 Gigabytes). Since useful manuals are always small, this is not a problem in practice. Parsing
is aborted as soon as the condition is detected.
®.br (roff) An ASCII control character supported by other roff(7) implementations but not by mandoc was
found in an input file. It is replaced by a question mark.
®.br (roff) An input file contains a roff(7) request supported by GNU troff or Heirloom troff but not by
mandoc, and it is likely that this will cause information loss or considerable misformatting.
®.br (eqn, tbl) The options line of a table defines equation delimiters. Any equation source code
contained in the table will be printed unformatted.
®.br (tbl) A table layout specification contains an ‘m’ modifier. The modifier is discarded.
®.br (tbl, mdoc, man) A table contains an invocation of an mdoc(7) or man(7) macro or of an undefined
macro. The macro is ignored, and its arguments are handled as if they were a text line.
SEE ALSO
apropos(1), man(1), eqn(7), man(7), mandoc_char(7), mdoc(7), roff(7), tbl(7)
HISTORY
The mandoc utility first appeared in OpenBSD 4.8. The option -I appeared in OpenBSD 5.2, and
-aCcfhKklMSsw in OpenBSD 5.7.
AUTHORS
The mandoc utility was written by Kristaps Dzonsons <kristaps@bsd.lv> and is maintained by Ingo Schwarze
<schwarze@openbsd.org>.
Debian July 20, 2017 MANDOC(1)