MANDOC(1) BSD General Commands Manual MANDOC(1)
NAME
mandoc -- format and display UNIX manuals
SYNOPSIS
mandoc [-acfhklV] [-Ios=name] [-Kencoding] [-mformat] [-Ooption] [-Toutput] [-Wlevel] [file ...]
DESCRIPTION
The mandoc utility formats UNIX manual pages for display.
By default, mandoc reads mdoc(7) or man(7) text from stdin, implying -mandoc, and produces -Tlocale 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 spec-
ified to override -a.
-f A synonym for whatis(1). This overrides any earlier -k and -l options.
-Ios=name
Override the default operating system name for the mdoc(7) 'Os' macro.
-h Display only the SYNOPSIS lines. Implies -c.
-Kencoding
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:
utf-8 if the first three bytes of the input file are the UTF-8 byte order mark (BOM, 0xefbbbf)
encoding if the first or second line of the input file matches the emacs mode line format
." -*- [...;] coding: encoding; -*-
utf-8 if the first non-ASCII byte in the file introduces a valid UTF-8 sequence
iso-8859-1 otherwise
-k A synonym for apropos(1). This overrides any earlier -f and -l options.
-l A synonym for -a. Also reverts any earlier -f and -k options.
-mformat
Input format. See Input Formats for available formats. Defaults to -mandoc.
-Ooption
Comma-separated output options.
-Toutput
Output format. See Output Formats for available formats. Defaults to -Tlocale.
-V Print version and exit.
-Wlevel
Specify the minimum message level to be reported on the standard error output and to affect the exit status. The level can be
warning, error, or fatal. The default is -Wfatal; -Wall is an alias for -Wwarning. See EXIT STATUS and DIAGNOSTICS for details.
The special option -Wstop 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 -Werror,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.
In -f and -k mode, mandoc also supports the options -CMmOSsw described in the apropos(1) manual.
Input Formats
The mandoc utility accepts mdoc(7) and man(7) input with -mdoc and -man, respectively. The mdoc(7) format is strongly recommended; man(7)
should only be used for legacy manuals.
A third option, -mandoc, which is also the default, determines encoding on-the-fly: if the first non-comment macro is 'Dd' or 'Dt', the
mdoc(7) parser is used; otherwise, the man(7) parser is used.
If multiple files are specified with -mandoc, each has its file-type determined this way. If multiple files are specified and -mdoc or -man
is specified, then this format is used exclusively.
Output Formats
The mandoc utility accepts the following -T arguments, which correspond to output modes:
-Tascii Produce 7-bit ASCII output. See ASCII Output.
-Thtml Produce HTML5, CSS1, and MathML output. See HTML Output.
-Tlint Parse only: produce no output. Implies -Wwarning.
-Tlocale Encode output using the current locale. This is the default. See Locale Output.
-Tman Produce man(7) format output. See Man Output.
-Tpdf Produce PDF output. See PDF Output.
-Tps Produce PostScript output. See PostScript Output.
-Ttree Produce an indented parse tree.
-Tutf8 Encode output in the UTF-8 multi-byte format. See UTF-8 Output.
-Txhtml This is a synonym for -Thtml.
If multiple input files are specified, these will be processed by the corresponding filter in-order.
ASCII Output
Output produced by -Tascii 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. If no equivalent is found, '?' is used
instead.
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, which will normalise to >=60.
HTML Output
Output produced by -Thtml conforms to HTML5 using optional self-closing tags. Default styles use only CSS1. Equations rendered from eqn(7)
blocks use MathML.
The example.style.css file documents style-sheet classes available for customising output. If a style-sheet is not specified with -Ostyle,
-Thtml 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 -Tlocale. 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 -Tascii. 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) format-
ters.
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.
PDF Output
PDF-1.1 output may be generated by -Tpdf. See PostScript Output for -O arguments and defaults.
PostScript Output
PostScript "Adobe-3.0" Level-2 pages may be generated by -Tps. Output pages default to letter sized and are rendered in the Times font fam-
ily, 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 -Tutf8 to force a UTF-8 locale. See Locale Output for details and options.
ENVIRONMENT
MANPAGER Any non-empty value of the environment variable MANPAGER will be used instead of the standard pagination program, more(1).
PAGER Specifies the pagination program to use when MANPAGER is not defined. If neither PAGER nor MANPAGER is defined, /usr/bin/more -s
will be used.
EXIT STATUS
The mandoc utility exits with one of the following values, controlled by the message level associated with the -W option:
0 No warnings or errors occurred, or those that did were ignored because they were lower than the requested level.
2 At least one warning occurred, but no error, and -Wwarning was specified.
3 At least one parsing error occurred, but no fatal error, and -Werror or -Wwarning was specified.
4 A fatal parsing error occurred.
5 Invalid command line arguments were specified. No input files have been read.
6 An operating system error occurred, for example memory exhaustion or an error accessing input files. Such errors cause mandoc to
exit at once, possibly in the middle of parsing or formatting a file.
Note that selecting -Tlint output mode implies -Wwarning.
EXAMPLES
To page manuals to the terminal:
$ mandoc -Wall,stop mandoc.1 2>&1 | less
$ mandoc mandoc.1 mdoc.3 mdoc.7 | less
To produce HTML manuals with style.css as the style-sheet:
$ mandoc -Thtml -Ostyle=style.css mdoc.7 > mdoc.7.html
To check over a large set of manuals:
$ mandoc -Tlint `find /usr/src -name *.[1-9]`
To produce a series of PostScript manuals for A4 paper:
$ mandoc -Tps -Opaper=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 -Tman foo.mdoc > foo.man
DIAGNOSTICS
Messages displayed by mandoc follow this format:
mandoc: file:line:column: level: message: macro args
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. 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:
syserr Opening or reading an input file failed, so the parser cannot even be started and no output is produced from that input file.
fatal The parser is unable to parse a given input file at all. No formatted output is produced from that input file.
error An input file contains syntax that cannot be safely interpreted, either because it is invalid or because mandoc does not implement
it yet. By discarding part of the input or inserting missing tokens, the parser is able to continue, and the error does not prevent
generation of formatted output, but typically, preparing that output involves information loss, broken document structure or unin-
tended formatting.
warning An input file uses obsolete, discouraged or non-portable syntax. All the same, the meaning of the input is unambiguous and a cor-
rect rendering can be produced. Documents causing warnings may render poorly when using other formatting tools instead of mandoc.
Messages of the warning and error levels are hidden unless their level, or a lower level, is requested using a -W option or -Tlint output
mode.
Warnings related to the document prologue
missing manual title, using UNTITLED
(mdoc) A Dt macro has no arguments, or there is no Dt macro before the first non-prologue macro.
missing manual title, using ""
(man) There is no TH macro, or it has no arguments.
lower case character in document title
(mdoc, man) The title is still used as given in the Dt or TH macro.
missing manual section, using ""
(mdoc, man) A Dt or TH macro lacks the mandatory section argument.
unknown manual section
(mdoc) The section number in a Dt line is invalid, but still used.
missing date, using today's date
(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 docu-
ment 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.
cannot parse date, using it verbatim
(mdoc, man) The date given in a Dd or TH macro does not follow the conventional format.
missing Os macro, using ""
(mdoc) The default or current system is not shown in this case.
duplicate prologue macro
(mdoc) One of the prologue macros occurs more than once. The last instance overrides all previous ones.
late prologue macro
(mdoc) A Dd or Os macro occurs after some non-prologue macro, but still takes effect.
skipping late title macro
(mdoc) The Dt macro can only occur before the first non-prologue macro because traditional formatters 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.
prologue macros out of order
(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
.so is fragile, better use ln(1)
(roff) Including files only works when the parser program runs with the correct current working directory.
no document body
(mdoc, man) The document body contains neither text nor macros. An empty document is shown, consisting only of a header and a footer line.
content before first section header
(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.
first section is not NAME
(mdoc) The argument of the first Sh macro is not 'NAME'. This may confuse makewhatis(8) and apropos(1).
bad NAME section contents
(mdoc) The last node in the NAME section is not an Nd macro, or any preceding macro is not Nm, or the NAME section is completely empty. This
may confuse makewhatis(8) and apropos(1).
sections out of conventional order
(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.
duplicate section title
(mdoc) The same standard section title occurs more than once.
unexpected section
(mdoc) A standard section header occurs in a section of the manual where it normally isn't useful.
unusual Xr order
(mdoc) In the SEE ALSO section, an Xr macro with a lower section number follows one with a higher number, or two Xr macros refering to the
same section are out of alphabetical order.
unusual Xr punctuation
(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.
AUTHORS section without An macro
(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
obsolete macro
(mdoc) See the mdoc(7) manual for replacements.
macro neither callable nor escaped
(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 line; otherwise, escape it by prepending '&'.
skipping paragraph macro
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
moving paragraph macro out of list
(mdoc) A list item in a Bl list contains a trailing paragraph macro. The paragraph macro is moved after the end of the list.
skipping no-space macro
(mdoc) An input line begins with an Ns macro. The macro is ignored.
blocks badly nested
(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.
nested displays are not portable
(mdoc) A Bd, D1, or Dl display occurs nested inside another Bd display. This works with mandoc, but fails with most other implementations.
moving content out of list
(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.
.Vt block has child macro
(mdoc) The Vt macro supports plain text arguments only. Formatting may be ugly and semantic searching for the affected content might not
work.
fill mode already enabled, skipping
(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.
fill mode already disabled, skipping
(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.
line scope broken
(man) While parsing the next-line scope of the previous macro, another macro is found that prematurely terminates the previous one. The pre-
vious, interrupted macro is deleted from the parse tree.
Warnings related to missing arguments
skipping empty request
(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.
conditional request controls empty scope
(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.
skipping empty macro
(mdoc) The indicated macro has no arguments and hence no effect.
empty argument, using 0n
(mdoc) The required width is missing after Bd or Bl -offset or -width.
argument count wrong
(mdoc, man) The indicated macro has too few or too many arguments. The syntax tree will contain the wrong number of arguments as given.
Formatting behaviour depends on the specific macro in question. Note that the same message may also occur as an ERROR, see below.
missing display type, using -ragged
(mdoc) The Bd macro is invoked without the required display type.
list type is not the first argument
(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.
missing -width in -tag list, using 8n
(mdoc) Every Bl macro having the -tag argument requires -width, too.
missing utility name, using ""
(mdoc) The Ex -std macro is called without an argument before Nm has first been called with an argument.
empty head in list item
(mdoc) In a Bl -diag, -hang, -inset, -ohang, or -tag list, an It macro lacks the required argument. The item head is left empty.
empty list item
(mdoc) In a Bl -bullet, -dash, -enum, or -hyphen list, an It block is empty. An empty list item is shown.
missing font type
(mdoc) A Bf macro has no argument. It switches to the default font, fR.
unknown font type
(mdoc) The Bf argument is invalid. The default font fR is used instead.
nothing follows prefix
(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 particu-
lar, spacing is not suppressed before the text or macros following on the next input line.
missing -std argument, adding it
(mdoc) An Ex or Rv macro lacks the required -std argument. The mandoc utility assumes -std even when it is not specified, but other imple-
mentations may not.
missing eqn box, using ""
(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
unterminated quoted argument
(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.
duplicate argument
(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.
skipping duplicate argument
(mdoc) An An macro has more than one -split or -nosplit argument. All but the first of these arguments are ignored.
skipping duplicate display type
(mdoc) A Bd macro has more than one type argument; the first one is used.
skipping duplicate list type
(mdoc) A Bl macro has more than one type argument; the first one is used.
skipping -width argument
(mdoc) A Bl -column, -diag, -ohang, -inset, or -item list has a -width argument. That has no effect.
unknown AT&T UNIX version
(mdoc) An At macro has an invalid argument. It is used verbatim, with "AT&T UNIX " prefixed to it.
comma in function argument
(mdoc) An argument of an Fa or Fn macro contains a comma; it should probably be split into two arguments.
parenthesis in function name
(mdoc) The first argument of an Fc or Fn macro contains an opening or closing parenthesis; that's probably wrong, parentheses are added auto-
matically.
invalid content in Rs block
(mdoc) An Rs block contains plain text or non-% macros. The bogus content is left in the syntax tree. Formatting may be poor.
invalid Boolean argument
(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, caus-
ing it to toggle the spacing mode.
unknown font, skipping request
(man, tbl) A roff(7) ft request or a tbl(7) f layout modifier has an unknown font argument.
Warnings related to plain text
blank line in fill mode, using .sp
(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.
tab in filled text
(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.
whitespace at end of input line
(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.
bad comment style
(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.
invalid escape sequence
(roff) An escape sequence has an invalid opening argument delimiter, lacks the closing argument delimiter, or the argument has too few char-
acters. If the argument is incomplete, * and
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.
undefined string, using ""
(roff) If a string is used without being defined before, its value is implicitly set to the empty string. However, defining strings explic-
itly before use keeps the code more readable.
Errors related to equations
unexpected equation scope closure
equation scope open on exit
overlapping equation scopes
unexpected end of equation
Errors related to tables
bad table syntax
bad table option
bad table layout
no table layout cells specified
no table data cells specified
ignore data in cell
data block still open
ignoring extra data cells
Errors related to roff, mdoc, and man code
input stack limit exceeded, infinite loop?
(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.
skipping bad character
(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.
skipping unknown macro
(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 argu-
ments.
skipping item outside list
(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.
skipping column outside column list
(mdoc) A Ta macro occurs outside any Bl -column block. It is discarded including its arguments.
skipping end of block that is not open
(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) RE or UE macro, an eqn(7) right delimiter or closing brace, or the end of an equation, table, or roff(7) condi-
tional request is encountered but no matching block is open. The offending request or macro is discarded.
inserting missing end of block
(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.
scope open on exit
(mdoc, man, eqn, tbl, roff) At the end of the document, an explicit mdoc(7) block, a man(7) next-line scope or RS or UR block, an equation,
table, or roff(7) conditional or ignore block is still open. The open block is closed implicitly.
escaped character not allowed in a name
(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.
argument count wrong
(mdoc, man, roff) The indicated request or macro has too few or too many arguments. The syntax tree will contain the wrong number of argu-
ments as given. Formatting behaviour depends on the specific request or macro in question. Note that the same message may also occur as a
WARNING, see above.
NOT IMPLEMENTED: Bd -file
(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.
missing list type, using -item
(mdoc) A Bl macro fails to specify the list type.
missing manual name, using ""
(mdoc) The first call to Nm lacks the required argument.
uname(3) system call failed, using UNKNOWN
(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"".
unknown standard specifier
(mdoc) An St macro has an unknown argument and is discarded.
skipping request without numeric argument
(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.
skipping all arguments
(mdoc, man, eqn, roff) An mdoc(7) Bt, Ed, Ef, Ek, El, Re, 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) '..' block closing request is invoked with at least one argument. All arguments are
ignored.
skipping excess arguments
(mdoc, roff) The Bf macro is invoked with more than one argument, or a request of the de family is invoked with more than two arguments. The
excess arguments are ignored.
FATAL errors
input too large
(mdoc, man) Currently, mandoc cannot handle input files larger than its arbitrary size limit of 2^31 bytes (2 Gigabytes). Since useful manu-
als are always small, this is not a problem in practice. Parsing is aborted as soon as the condition is detected.
NOT IMPLEMENTED: .so with absolute path or ".."
(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. The parser exits immediately.
.so request failed
(roff) Servicing a so request requires reading an external file. While trying to do so, an open(2), stat(2), or read(2) system call failed.
The parser exits immediately. Before showing this message, mandoc always shows another message explaining why the system call failed.
COMPATIBILITY
This section summarises mandoc compatibility with GNU troff. Each input and output format is separately noted.
ASCII Compatibility
o Unrenderable unicode codepoints specified with '[uNNNN]' escapes are printed as '?' in mandoc. In GNU troff, these raise an error.
o The 'Bd -literal' and 'Bd -unfilled' macros of mdoc(7) in -Tascii are synonyms, as are -filled and -ragged.
o In historic GNU troff, the 'Pa' mdoc(7) macro does not underline when scoped under an 'It' in the FILES section. This behaves correctly
in mandoc.
o A list or display following the 'Ss' mdoc(7) macro in -Tascii does not assert a prior vertical break, just as it doesn't with 'Sh'.
o The 'na' man(7) macro in -Tascii has no effect.
o Words aren't hyphenated.
HTML Compatibility
o The 'fP' escape will revert the font to the previous 'f' escape, not to the last rendered decoration, which is now dictated by CSS
instead of hard-coded. It also will not span past the current scope, for the same reason. Note that in ASCII Output mode, this will
work fine.
o The mdoc(7) 'Bl -hang' and 'Bl -tag' list types render similarly (no break following overreached left-hand side) due to the expressive
constraints of HTML.
o The man(7) 'IP' and 'TP' lists render similarly.
SEE ALSO
eqn(7), man(7), mandoc_char(7), mdoc(7), roff(7), tbl(7)
AUTHORS
The mandoc utility was written by Kristaps Dzonsons <kristaps@bsd.lv>.
CAVEATS
In -Thtml and -Txhtml, the maximum size of an element attribute is determined by BUFSIZ, which is usually 1024 bytes. Be aware of this when
setting long link formats such as -Ostyle=really/long/link.
Nesting elements within next-line element scopes of -man, such as 'br' within an empty 'B', will confuse -Thtml and -Txhtml and cause them to
forget the formatting of the prior next-line scope.
The ''' control character is an alias for the standard macro control character and does not emit a line-break as stipulated in GNU troff.
BSD
December 2, 2014 BSD