TODO

   1 ************************************************************************
   2 * Official mandoc TODO.
   3 * $Id: TODO,v 1.254 2018/05/25 20:23:51 schwarze Exp $
   4 ************************************************************************
   5
   6 Many issues are annotated for difficulty as follows:
   7
   8  - loc = locality of the issue
   9     *    single file issue, affects file only, or very few
  10     **   single module issue, affects several files of one module
  11     ***  cross-module issue, significantly impacts multiple modules
  12          and may require substantial changes to internal interfaces
  13  - exist = difficulty of the existing code in this area
  14     *    affected code is straightforward and easy to read and change
  15     **   affected code is somewhat complex, but once you understand
  16          the design, not particularly difficult to understand
  17     ***  affected code uses a special, exceptionally tricky design
  18  - algo = difficulty of the new algorithm to be written
  19     *    the required logic and code is straightforward
  20     **   the required logic is somewhat complex and needs a careful design
  21     ***  the required logic is exceptionally tricky,
  22          maybe an approach to solve that is not even known yet
  23  - size = the amount of code to be written or changed
  24     *    a small number of lines (at most 100, usually much less)
  25     **   a considerable amount of code (several dozen to a few hundred)
  26     ***  a large amount of code (many hundreds, maybe thousands)
  27  - imp = importance of the issue
  28     *    mostly for completeness
  29     **   would be nice to have
  30     ***  issue causes considerable inconvenience
  31
  32 Obviously, as the issues have not been solved yet, these annotations
  33 are mere guesses, and some may be wrong.
  34
  35 ************************************************************************
  36 * missing features
  37 ************************************************************************
  38
  39 --- missing roff features ----------------------------------------------
  40
  41 - .ad (adjust margins)
  42   .ad l -- adjust left margin only (flush left)
  43   .ad r -- adjust right margin only (flush right)
  44   .ad c -- center text on line
  45   .ad b -- adjust both margins (alias: .ad n)
  46   .na   -- temporarily disable adjustment without changing the mode
  47   .ad   -- re-enable adjustment without changing the mode
  48   Adjustment mode is ignored while in no-fill mode (.nf).
  49   loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
  50
  51 - .fc (field control)
  52   found by naddy@ in xloadimage(1)
  53   loc **  exist ***  algo *  size *  imp *
  54
  55 - .ns (no-space mode) occurs in xine-config(1)
  56   when implementing this, also let .TH set it
  57   reported by brad@  Sat, 15 Jan 2011 15:45:23 -0500
  58   loc ***  exist ***  algo ***  size **  imp *
  59
  60 - .while and .shift
  61   found by jca@ in ratpoison(1)  Sun, 30 Jun 2013 12:01:09 +0200
  62   loc *  exist **  algo **  size **  imp **
  63
  64 - \w'' improve width measurements
  65   would not be very useful without an expression parser, see below
  66   needed for Tcl_NewStringObj(3) via wiz@  Wed, 5 Mar 2014 22:27:43 +0100
  67   loc **  exist ***  algo ***  size *  imp ***
  68
  69 - \\ in high-level macro arguments
  70   Currently, \\ is expanded in two situations:
  71   1) macro and string definition (roff.c setstrn())
  72   2) macro argument parsing (mandoc.c mandoc_getarg())
  73   For user defined macros, the second happens in time because of ROFF_REPARSE.
  74   But for standard high-level macros, it only happens after entering the
  75   high level parsers, which is too late because the code doesn't get
  76   back to roff.c roff_res() from that point.  Because this requires
  77   distinguishing requests, user-defined macros and standard macros
  78   on the roff_res() level, it is hard to solve without the parser reorg.
  79   Found by naddy@ in devel/cutils cobfusc(1)  Mon, 16 Feb 2015 19:10:52 +0100
  80   loc ***  exist ***  algo ***  size **  imp *
  81
  82 - check for missing roff escape sequences, implement those that are
  83   trivial even if not usually appearing in manual pages, gracefully
  84   ignore the non-trivial ones, document what they are supposed to do
  85   and what mandoc does instead
  86   loc *  exist **  algo *  size *  imp *
  87
  88 --- missing mdoc features ----------------------------------------------
  89
  90 - .Bl -column .Xo support is missing
  91   ultimate goal:
  92   restore .Xr and .Dv to
  93   lib/libc/compat-43/sigvec.3
  94   lib/libc/gen/signal.3
  95   lib/libc/sys/sigaction.2
  96   loc *  exist ***  algo ***  size *  imp **
  97
  98 - edge case: decide how to deal with blk_full bad nesting, e.g.
  99   .Sh .Nm .Bk .Nm .Ek .Sh found by jmc@ in ssh-keygen(1)
 100   from jmc@  Wed, 14 Jul 2010 18:10:32 +0100
 101   loc *  exist ***  algo ***  size **  imp **
 102
 103 - .Bd -centered implies -filled, not -unfilled, which is not
 104   easy to implement; it requires code similar to .ce, which
 105   we don't have either.
 106   Besides, groff has bug causing text right *before* .Bd -centered
 107   to be centered as well.
 108   loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
 109
 110 - .Bd -filled should not be the same as .Bd -ragged, but align both
 111   the left and right margin.  In groff, it is implemented in terms
 112   of .ad b, which we don't have either.  Found in cksum(1).
 113   loc ***  exist ***  algo **  size **  imp **  (parser reorg would help)
 114
 115 - implement blank `Bl -column', such as
 116   .Bl -column
 117   .It foo Ta bar
 118   .El
 119   loc *  exist ***  algo ***  size *  imp *
 120
 121 - explicitly disallow nested `Bl -column', which would clobber internal
 122   flags defined for struct mdoc_macro
 123   loc *  exist *  algo *  size *  imp **
 124
 125 - In .Bl -column .It, the end of the line probably has to be regarded
 126   as an implicit .Ta, if there could be one, see the following mildly
 127   ugly code from login.conf(5):
 128     .Bl -column minpasswordlen program xetcxmotd
 129     .It path Ta path Ta value of Dv _PATH_DEFPATH
 130     .br
 131     Default search path.
 132   reported by Michal Mazurek <akfaew at jasminek dot net>
 133   via jmc@ Thu, 7 Apr 2011 16:00:53 +0059
 134   loc *  exist ***  algo **  size *  imp **
 135
 136 - inside `.Bl -column' phrases, punctuation is handled like normal
 137   text, e.g. `.Bl -column .It Fl x . Ta ...' should give "-x -."
 138
 139 - inside `.Bl -column' phrases, TERMP_IGNDELIM handling by `Pf'
 140   is not safe, e.g. `.Bl -column .It Pf a b .' gives "ab."
 141   but should give "ab ."
 142
 143 - check whether it is correct that `D1' uses INDENT+1;
 144   does it need its own constant?
 145   loc *  exist **  algo **  size *  imp **
 146
 147 - prohibit `Nm' from having non-text HEAD children
 148   (e.g., NetBSD mDNSShared/dns-sd.1)
 149   (mdoc_html.c and mdoc_term.c `Nm' handlers can be slightly simplified)
 150
 151 - support translated section names
 152   e.g. x11/scrotwm scrotwm_es.1:21:2: error: NAME section must be first
 153   that one uses NOMBRE because it is spanish...
 154   deraadt tends to think that section-dependent macro behaviour
 155   is a bad idea in the first place, so this may be irrelevant
 156   loc **  exist **  algo **  size *  imp **
 157
 158 - When there is free text in the SYNOPSIS and that free text contains
 159   the .Nm macro, groff somehow understands to treat the .Nm as an in-line
 160   macro, while mandoc treats it as a block macro and breaks the line.
 161   No idea how the logic for distinguishing in-line and block instances
 162   should be, needs investigation.
 163   uqs@  Thu, 2 Jun 2011 11:03:51 +0200
 164   uqs@  Thu, 2 Jun 2011 11:33:35 +0200
 165   loc *  exist **  algo ***  size *  imp **
 166
 167 --- missing man features -----------------------------------------------
 168
 169 - groff_www(7) .MTO and .URL
 170   These macros were used by the GNU grep(1) man page.
 171   We should probably *not* add them to mandoc.
 172   Just mentioning this here to keep track of the abuse.
 173   Laura Morales <lauretas at mail dot com> 20 Apr 2018 07:33:02 +0200
 174   loc **  exist *  algo *  size **  imp *
 175
 176 --- missing tbl features -----------------------------------------------
 177
 178 - the "s" layout column specifier is used for placement of data
 179   into columns, but ignored during column width calculations
 180   synaptics(4) found by tedu@  Mon, 17 Aug 2015 21:17:42 -0400
 181   loc *  exist **  algo ***  size *  imp **
 182
 183 - support mdoc(7) and man(7) macros inside tbl(7) code;
 184   probably requires the parser reorg and letting tbl(7)
 185   use roff_node such that macro sets can mix;
 186   informed by bapt@ that FreeBSD needs this: 3 Jan 2015 23:32:23 +0100
 187   loc ***  exist **  algo ***  size **  imp ***
 188
 189 - look at the POSIX manuals in the books/man-pages-posix port,
 190   they use some unsupported tbl(7) features.
 191   loc *  exist **  algo **  size **  imp ***
 192
 193 - look what Joerg Schilling manual pages use
 194   Thu, 19 Mar 2015 18:31:48 +0100
 195
 196 - use Unicode U+2500 to U+256C for table borders
 197   in tbl(7) -Tutf-8 output
 198   suggested by bentley@  Tue, 14 Oct 2014 04:10:55 -0600
 199   loc *  exist **  algo *  size *  imp **
 200
 201 --- missing eqn features -----------------------------------------------
 202
 203 - In a matrix, break the output line after each matrix line.
 204   Found in the discussion at CDBUG 2015.
 205   Suggested by Avi Weinstock.
 206   loc *  exist *  algo *  size *  imp **
 207
 208 - The "size" keyword is parsed, but ignored by the formatter.
 209   loc *  exist *  algo *  size *  imp *
 210
 211 - The spacing characters `~', `^', and tab are currently ignored,
 212   see User's Guide (Second Edition) page 2 section 4.
 213   loc *  exist *  algo **  size *  imp **
 214
 215 - Mark and lineup are parsed and ignored,
 216   see User's Guide (Second Edition) page 5 section 15.
 217   loc **  exist **  algo **  size **  imp **
 218
 219 - GNU eqn converts some operators to special characters, for example,
 220   input HYPHEN-MINUS becomes output \(mi, unless it is part of a
 221   quoted word.  mandoc(1) only does this when the operator is
 222   surrounded by blanks, not when it is part of an unquoted word.
 223   Also, check whether there are more such cases (e.g., +?).
 224   reported by bentley@  20 Jun 2017 02:04:29 -0600
 225   loc *  exist **  algo **  size *  imp *
 226
 227 - Primes, opprime, and '
 228   bentley@  Thu, 13 Jul 2017 23:14:20 -0600
 229
 230 --- missing misc features ----------------------------------------------
 231
 232 - italic correction (\/) in PostScript mode
 233   Werner LEMBERG on groff at gnu dot org  Sun, 10 Nov 2013 12:47:46
 234   loc **  exist **  algo *  size *  imp *
 235
 236 - change the default PAGER to more -Es and use the pager
 237   even for apropos title line output; req by bapt@
 238   loc *  exist *  algo *  size *  imp ***
 239
 240 - clean up escape sequence handling, creating three classes:
 241   (1) fully implemented, or parsed and ignored without loss of content
 242   (2) unimplemented, potentially causing loss of content
 243       or serious mangling of formatting (e.g. \n) -> ERROR
 244       see textproc/mgdiff(1) for nice examples
 245   (3) undefined, just output the character -> perhaps WARNING
 246   loc ***  exist **  algo **  size **  imp *** (parser reorg helps)
 247
 248 - kettenis wants base roff, ms, and me  Fri, 1 Jan 2010 22:13:15 +0100 (CET)
 249   loc **  exist **  algo **  size ***  imp *
 250
 251 --- compatibility checks -----------------------------------------------
 252
 253 - is .Bk implemented correctly in modern groff?
 254   sobrado@  Tue, 19 Apr 2011 22:12:55 +0200
 255
 256 - compare output to Heirloom roff, Solaris roff, and
 257   http://repo.or.cz/w/neatroff.git  http://litcave.rudi.ir/
 258
 259 - look at AT&T DWB http://www2.research.att.com/sw/download
 260   Carsten Kunze <carsten dot kunze at arcor dot de> has patches
 261   Mon, 4 Aug 2014 17:01:28 +0200
 262   ported version: https://github.com/n-t-roff/DWB3.3
 263   Carsten Kunze  Wed, 22 Apr 2015 11:21:43 +0200
 264
 265 - look at pages generated from reStructeredText, e.g. devel/mercurial hg(1)
 266   These are a weird mixture of man(7) and custom autogenerated low-level
 267   roff stuff.  Figure out to what extent we can cope.
 268   For details, see http://docutils.sourceforge.net/rst.html
 269   noted by stsp@  Sat, 24 Apr 2010 09:17:55 +0200
 270   reminded by nicm@  Mon, 3 May 2010 09:52:41 +0100
 271
 272 - look at pages generated from ronn(1) github.com/rtomayko/ronn
 273   (based on markdown)
 274
 275 - look at pages generated from Texinfo source by yat2m, e.g. security/gnupg
 276   First impression is not that bad.
 277
 278 - look at pages generated by pandoc; see
 279   https://github.com/jgm/pandoc/blob/master/src/Text/Pandoc/Writers/Man.hs
 280   porting planned by kili@  Thu, 19 Jun 2014 19:46:28 +0200
 281
 282 - check compatibility with Plan9:
 283   http://swtch.com/usr/local/plan9/tmac/tmac.an
 284   http://swtch.com/plan9port/man/man7/man.html
 285   "Anthony J. Bentley" <anthonyjbentley@gmail.com> 28 Dec 2010 21:58:40 -0700
 286
 287 - check compatibility with COHERENT troff:
 288   http://www.nesssoftware.com/home/mwc/source.php
 289
 290 - check compatibility with the man(7) formatter
 291   https://raw.githubusercontent.com/rofl0r/hardcore-utils/master/man.c
 292
 293 - check compatibility with
 294   http://ikiwiki.info/plugins/contrib/mandoc/
 295   https://github.com/schmonz/ikiwiki/compare/mandoc
 296   Amitai Schlair  Mon, 19 May 2014 14:05:53 -0400
 297
 298 - check features of the Slackware man.conf(5) format
 299   Carsten Kunze  Wed, 11 Mar 2015 17:57:24 +0100
 300
 301 ************************************************************************
 302 * formatting issues: ugly output
 303 ************************************************************************
 304
 305 - revisit empty in-line macros
 306   look at the difference between "Em x Em ." and "Sq x Em ."
 307   Carsten Kunze  Fri, 12 Dec 2014 00:15:41 +0100
 308   loc *** exist *** algo *** size * imp **
 309
 310 - a column list with blank `Ta' cells triggers a spurious
 311   start-with-whitespace printing of a newline
 312
 313 - In .Bl -column, .It a<tab>"b<tab>c"
 314   shows the quotes in groff, but not in mandoc
 315   loc * exist *** algo ** size * imp **
 316
 317 - In .Bl -column,
 318   .It Em Authentication<tab>Key Length
 319   ought to render "Key Length" with emphasis, too,
 320   see OpenBSD iked.conf(5).
 321   reported again Nicolas Joly via wiz@ Wed, 12 Oct 2011 00:20:00 +0200
 322   loc *  exist ***  algo ***  size **  imp ***
 323
 324 - empty phrases in .Bl column produce too few blanks
 325   try e.g. .Bl -column It Ta Ta
 326   reported by millert Fri, 02 Apr 2010 16:13:46 -0400
 327   loc *  exist ***  algo ***  size *  imp **
 328
 329 - .%T can have trailing punctuation.  Currently, it puts the trailing
 330   punctuation into a trailing MDOC_TEXT element inside its own scope.
 331   That element should rather be outside its scope, such that the
 332   punctuation does not get underlines.  This is not trivial to
 333   implement because .%T then needs some features of in_line_eoln() -
 334   slurp all arguments into one single text element - and one feature
 335   of in_line() - put trailing punctuation out of scope.
 336   Found in mount_nfs(8) and exports(5), search for "Appendix".
 337   loc **  exist **  algo ***  size *  imp **
 338
 339 - Trailing punctuation after .%T triggers EOS spacing, at least
 340   outside .Rs (eek!).  Simply setting ARGSFL_DELIM for .%T is not
 341   the right solution, it sends mandoc into an endless loop.
 342   reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
 343   loc *  exist **  algo **  size *  imp **
 344
 345 - global variables in the SYNOPSIS of section 3 pages
 346   .Vt vs .Vt/.Va vs .Ft/.Va vs .Ft/.Fa ...
 347   from kristaps@  Tue, 08 Jun 2010 11:13:32 +0200
 348
 349 - implicit whitespace around inline equations
 350   example code:  where '$times$' denotes matrix multiplication
 351   must not have an HTML line break, nor a blank, before <math>
 352   partial solution: html.c {"math", HTML_NLINSIDE | HTML_INDENT},
 353   bentley@  Thu, 13 Jul 2017 19:00:59 -0600
 354
 355 - in enclosures, mandoc sometimes fancies a bogus end of sentence
 356   reminded by jmc@  Thu, 23 Sep 2010 18:13:39 +0059
 357   loc *  exist **  algo ***  size *  imp ***
 358
 359 - a line starting with "\fB something" counts as starting with whitespace
 360   and triggers a line break; found in audio/normalize-mp3(1)
 361   loc **  exist *  algo **  size *  imp **
 362
 363 - formatting /usr/local/man/man1/latex2man.1 with groff and mandoc
 364   reveals lots of bugs both in groff and mandoc...
 365   reported by bentley@  Wed, 22 May 2013 23:49:30 -0600
 366
 367 --- PostScript and PDF issues ------------------------------------------
 368
 369 - PDF output doesn't use a monospaced font for .Bd -literal
 370   Example: "mandoc -Tpdf afterboot.8 > output.pdf && pdfviewer output.pdf".
 371   Search the text "Routing tables".
 372   Also check what PostScript mode does when fixing this.
 373   reported by juanfra@ Wed, 04 Jun 2014 21:44:58 +0200
 374   instructions from juanfra@  Wed, 11 Jun 2014 02:21:01 +0200
 375     add a new <</Type /Font>> block to the PDF files with /BaseFont /Courier
 376     and change the /Name from /F0 to the new font (/F5 (?)).
 377   re-reported by tb@ Mon, 16 Mar 2015 16:47:21 +0100
 378   loc *  exist **  algo **  size *  imp **
 379
 380 --- HTML issues --------------------------------------------------------
 381
 382 - @media queries to reduce indentation on low-res displays
 383   some mails in the Viewport for man.openbsd.org thread
 384   e.g. Adam Thompson 24 May 2018 15:09:00 -0500
 385
 386 - wrap Sh and Ss content into <div>
 387   Laura Morales <lauretas at mail dot com> 21 Apr 2018 18:10:48 +0200
 388   (Evaluate whether this is really useful and has no adverse
 389    side effects before implementing; if it is possible,
 390    it does seem cleaner.)
 391   loc **  exist **  algo *  size *  imp ***
 392
 393 - format ".IP *" etc. as <ul> rather than <dl>
 394   https://github.com/Debian/debiman/issues/67
 395   loc ** exist ** algo ** size * imp ***
 396
 397 - .Bf at the beginning of a paragraph inserts a bogus 1ex horizontal
 398   space, see for example random(3).  Introduced in
 399   http://mdocml.bsd.lv/cgi-bin/cvsweb/mdoc_html.c.diff?r1=1.91&r2=1.92
 400   reported by deraadt@ Mon, 28 Sep 2015 20:14:13 -0600 (MDT)
 401   loc **  exist **  algo **  size *  imp *
 402
 403 - jsg on icb, Nov 3, 2014:
 404   try to guess Xr in man(7) for hyperlinking
 405   and render them with <a class="Xr" href=...>
 406   https://github.com/Debian/debiman/issues/15
 407   loc *  exist *  algo **  size **  imp **
 408
 409 - The tables used to render the three-part page headers actually force
 410   the width of the <body> to the max-width given for <html>.
 411   Not yet sure how to fix that...
 412   Observed by an Anonymous Coward on undeadly.org:
 413   http://undeadly.org/cgi?action=article&sid=20140925064244&pid=1
 414   loc *  exist *  algo **  size *  imp ***
 415
 416 - generate <img> tags in HTML
 417   idea from florian@  Tue, 7 Apr 2015 00:26:28 +0000
 418   may be possible to implement with .Lk img://something.png alt_text
 419
 420 - check https://github.com/trentm/mdocml
 421
 422 ************************************************************************
 423 * formatting issues: gratuitous differences
 424 ************************************************************************
 425
 426 - .Fn reopens a new scope after punctuation in mandoc,
 427   but closes its scope for good in groff.
 428   Do we want to change mandoc or groff?
 429   Steffen Nurpmeso  Sat, 08 Nov 2014 13:34:59 +0100
 430   loc *  exist **  algo **  size *  imp **
 431
 432 - In .Bl -enum -width 0n, groff continues one the same line after
 433   the number, mandoc breaks the line.
 434   mail to kristaps@  Mon, 20 Jul 2009 02:21:39 +0200
 435   loc *  exist **  algo **  size *  imp **
 436
 437 - .Pp between two .It in .Bl -column should produce one,
 438   not two blank lines, see e.g. login.conf(5).
 439   reported by jmc@  Sun, 17 Apr 2011 14:04:58 +0059
 440   reported again by sthen@  Wed, 18 Jan 2012 02:09:39 +0000 (UTC)
 441   loc *  exist ***  algo **  size *  imp **
 442
 443 - If the *first* line after .It is .Pp, break the line right after
 444   the tag, do not pad with space characters before breaking.
 445   See the description of the a, c, and i commands in sed(1).
 446   loc *  exist **  algo **  size *  imp **
 447
 448 - If the first line after .It is .D1, do not assert a blank line
 449   in between, see for example tmux(1).
 450   reported by nicm@  13 Jan 2011 00:18:57 +0000
 451   loc *  exist **  algo **  size *  imp **
 452
 453 - Trailing punctuation after .It should trigger EOS spacing.
 454   reported by Nicolas Joly  Sat, 17 Nov 2012 11:49:54 +0100
 455   Probably, this should be fixed somewhere in termp_it_pre(), not sure.
 456   loc *  exist **  algo **  size *  imp **
 457
 458 - When the -width string contains macros, the macros must be rendered
 459   before measuring the width, for example
 460     .Bl -tag -width ".Dv message"
 461   in magic(5), located in src/usr.bin/file, is the same
 462   as -width 7n, not -width 11n.
 463   The same applies to .Bl -column column widths;
 464   reported again by Nicolas Joly Thu, 1 Mar 2012 13:41:26 +0100 via wiz@ 5 Mar
 465   reported again by Franco Fichtner Fri, 27 Sep 2013 21:02:28 +0200
 466   reported again by Bruce Evans Fri, 17 Feb 2017 21:22:44 +0100 via bapt@
 467   loc ***  exist ***  algo ***  size **  imp ***
 468   An easy partial fix would be to just skip the first word if it starts
 469   with a dot, including any following white space, when measuring.
 470   loc *  exist *  algo *  size *  imp ***
 471
 472 - The \& zero-width character counts as output.
 473   That is, when it is alone on a line between two .Pp,
 474   we want three blank lines, not two as in mandoc.
 475   loc **  exist **  algo **  size *  imp **
 476
 477 - Sequences of multiple man(7) paragraphs (.PP, .IP) interspersed
 478   with .ps and .nf/.fi produce execessive blank lines, see libJudy
 479   and graphics/dcmtk.  The parser reorg may help with this.
 480
 481 - trailing whitespace must be ignored even when followed by a font escape,
 482   see for example
 483     makes
 484     \fBdig \fR
 485     operate in batch mode
 486   in dig(1).
 487   loc **  exist **  algo **  size *  imp **
 488
 489 ************************************************************************
 490 * warning issues
 491 ************************************************************************
 492
 493 - warn about duplicate .Sh/.Ss heads
 494   gre(4): Rename duplicate sections 20 Apr 2018 15:27:33 +0200
 495   loc *  exist *  algo *  size *  imp **
 496
 497 - style message about macros inside .Bd -literal and .Dl, in particular
 498   font changing macros like .Cm, .Ar, .Fa (from the mdoclint TODO)
 499
 500 - style message about mismatches between the section number in the
 501   file name (if it is known) and the section number in .Dt
 502   (from the mdoclint TODO)
 503
 504 - style message about NULL without .Dv (from the mdoclint TODO)
 505
 506 - style message about error constants without .Er (from the mdoclint TODO)
 507
 508 - warn when .Sh or .Ss contain other macros
 509   Steffen Nurpmeso, savannah.gnu.org/bugs/index.php?45034
 510   loc *  exist *  algo *  size *  imp **
 511
 512 - style message about violations of the convention
 513   .An name Aq Mt localpart@domain in AUTHORS (from the mdoclint TODO)
 514
 515 - warn about attempts to call non-callable macros
 516   Steffen Nurpmeso  Tue, 11 Nov 2014 22:55:16 +0100
 517   Note that formatting is inconsistent in groff.
 518   .Fn Po prints "Po()", .Ar Sh prints "file ..." and no "Sh".
 519   Relatively hard because the relevant code is scattered
 520   all over mdoc_macro.c and all subtly different.
 521   loc **  exist **  algo **  size **  imp **
 522
 523 - style message about suspicious uses of - vs. \- vs. \(mi
 524   e.g. -1 is likely wrong (from the mdoclint TODO)
 525
 526 - warn about punctuation - e.g. ',' and ';' - at the beginning
 527   of a text line, if it is likely intended to follow the preceding
 528   output without intervening whitespace, in particular after a
 529   macro line (from the mdoclint TODO)
 530
 531 - mandoc_special does not really check the escape sequence,
 532   but just the overall format
 533   loc **  exist **  algo ***  size **  imp **
 534
 535 ************************************************************************
 536 * documentation issues
 537 ************************************************************************
 538
 539 - dashes, hyphens, and minus signs in manual pages
 540   jmc@ Fri, 28 Mar 2014 07:19:27 +0000
 541
 542 - mark macros as: page structure domain, manual domain, general text domain
 543   is this useful?
 544
 545 - mention /usr/share/misc/mdoc.template in mdoc(7)?
 546
 547 - Is all the content from http://www.std.com/obi/BSD/doc/usd/28.tbl/tbl
 548   covered in tbl(7)?
 549
 550 ************************************************************************
 551 * performance issues
 552 ************************************************************************
 553
 554 - the PDF file is HUGE: this can be reduced by using relative offsets
 555
 556 ************************************************************************
 557 * structural issues
 558 ************************************************************************
 559
 560 - POSIX says in the documentation of sysconf(3) that PATH_MAX
 561   is allowed to be so large that it is a bad idea to use it
 562   for sizing static buffers.  So use dynamic buffers throughout.
 563   See the file test-PATH_MAX.c for details.
 564   Found by Aaron M. Ucko in the GNU Hurd via Bdale Garbee,
 565   https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=829624
 566
 567 - We use the input line number at several places to distinguish
 568   same-line from different-line input.  That plainly doesn't work
 569   with user-defined macros, leading to random breakage.
 570
 571 - Is it possible to further simplify ENDBODY_SPACE?
 572
 573 - Find better ways to prevent endless loops
 574   in roff(7) macro and string expansion.
 575
 576 - make buffers for parsing functions const
 577   christos@ via wiz@  Fri, 18 Dec 2015 17:10:01 +0100
 578
 579 - struct mparse refactoring
 580   Steffen Nurpmeso  Thu, 04 Sep 2014 12:50:00 +0200
 581
 582 ************************************************************************
 583 * CGI issues
 584 ************************************************************************
 585
 586  - Enable HTTP compression by detecting gzip encoding and filtering
 587    output through libz.
 588  - Sandbox (see OpenSSH).
 589  - Enable caching support via HTTP 304 and If-Modified-Since.
 590  - Have Mac OSX systems automatically disable -static compilation of the
 591    CGI: -static isn't supported.
 592
 593 ************************************************************************
 594 * to improve in the groff_mdoc(7) macros
 595 ************************************************************************
 596
 597 - .Cd # arch1, arch2 in section 4 pages:
 598   find better way to indicate multiple architectures, maybe:
 599   allow .Dt vgafb 4 "macppc sparc64"
 600   already shown as "Device Drivers Manual (macppc sparc64)"
 601   for apropos, make that "vgafb(4) - macppc # sparc64" instead of "- all"
 602   groff can be made to show multiple arches, too, but it is
 603   tedious to do the string parsing in roff code...
 604   jmc@ 23 Apr 2018 07:24:52 +0100 [man for vgafb(4)...]
 605   loc **  exist **  algo *  size *  imp ***
 606
 607 - use uname(1) to set doc-default-operating-system at install time
 608   tobimensch  Mon, 1 Dec 2014 00:25:07 +0100
 609
 610 - apostrophe (39), circumflex (94), grave (96), tilde (126)
 611   in manuals: \(aq, \(ha, \`, \(ti
 612   Re: [Groff] ASCII Minus Sign in man Pages.
 613   bentley@ 26 Apr 2017 10:02:06 -0600
 614   Do we need to fix existing manuals?
 615   Do we need to fix the definition of the mdoc(7) language?