[BACK]Return to mandoc.1 CVS log [TXT][DIR] Up to [cvsweb.bsd.lv] / mandoc

Diff for /mandoc/mandoc.1 between version 1.19 and 1.96

version 1.19, 2009/06/15 09:35:16 version 1.96, 2011/10/06 23:05:55
Line 1 
Line 1 
 .\"     $Id$  .\"     $Id$
 .\"  .\"
 .\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@kth.se>  .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\"  .\"
 .\" Permission to use, copy, modify, and distribute this software for any  .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above  .\" purpose with or without fee is hereby granted, provided that the above
Line 17 
Line 17 
 .Dd $Mdocdate$  .Dd $Mdocdate$
 .Dt MANDOC 1  .Dt MANDOC 1
 .Os  .Os
 .\" SECTION  
 .Sh NAME  .Sh NAME
 .Nm mandoc  .Nm mandoc
 .Nd format and display UNIX manuals  .Nd format and display UNIX manuals
 .\" SECTION  
 .Sh SYNOPSIS  .Sh SYNOPSIS
 .Nm mandoc  .Nm mandoc
 .Op Fl V  .Op Fl V
 .Op Fl f Ns Ar option...  
 .Op Fl m Ns Ar format  .Op Fl m Ns Ar format
 .Op Fl W Ns Ar err...  .Op Fl O Ns Ar option
 .Op Fl T Ns Ar output  .Op Fl T Ns Ar output
 .Op Ar infile...  .Op Fl W Ns Ar level
 .\" SECTION  .Op Ar
 .Sh DESCRIPTION  .Sh DESCRIPTION
 The  The
 .Nm  .Nm
 utility formats  utility formats
 .Ux  .Ux
 manual pages for display.  The arguments are as follows:  manual pages for display.
   The arguments are as follows:
 .Bl -tag -width Ds  .Bl -tag -width Ds
 .\" ITEM  
 .It Fl f Ns Ar option...  
 Override default compiler behaviour.  See  
 .Sx Compiler Options  
 for details.  
 .\" ITEM  
 .It Fl m Ns Ar format  .It Fl m Ns Ar format
 Input format.  See  Input format.
   See
 .Sx Input Formats  .Sx Input Formats
 for available formats.  Defaults to  for available formats.
 .Fl m Ns Ar andoc .  Defaults to
 .\" ITEM  .Fl m Ns Cm andoc .
   .It Fl O Ns Ar option
   Comma-separated output options.
 .It Fl T Ns Ar output  .It Fl T Ns Ar output
 Output format.  See  Output format.
   See
 .Sx Output Formats  .Sx Output Formats
 for available formats.  Defaults to  for available formats.
 .Fl T Ns Ar ascii .  Defaults to
 .\" ITEM  .Fl T Ns Cm ascii .
 .It Fl V  .It Fl V
 Print version and exit.  Print version and exit.
 .\" ITEM  .It Fl W Ns Ar level
 .It Fl W Ns Ar err...  Specify the minimum message
 Print warning messages.  May be set to  .Ar level
 .Fl W Ns Ar all  to be reported on the standard error output and to affect the exit status.
 for all warnings,  The
 .Ar compat  .Ar level
 for groff/troff-compatibility warnings, or  can be
 .Ar syntax  .Cm warning ,
 for syntax warnings.  If  .Cm error ,
 .Fl W Ns Ar error  or
 is specified, warnings are considered errors and cause utility  .Cm fatal .
 termination.  Multiple  The default is
 .Fl W  .Fl W Ns Cm fatal ;
 arguments may be comma-separated, such as  .Fl W Ns Cm all
 .Fl W Ns Ar error,all .  is an alias for
 .\" ITEM  .Fl W Ns Cm warning .
 .It Ar infile...  See
 Read input from zero or more  .Sx EXIT STATUS
 .Ar infile .  and
 If unspecified, reads from stdin.  If multiple files are specified,  .Sx DIAGNOSTICS
   for details.
   .Pp
   The special option
   .Fl W Ns Cm stop
   tells
 .Nm  .Nm
   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
   .Ar level
   and
   .Cm stop
   are requested, they can be joined with a comma, for example
   .Fl W Ns Cm error , Ns Cm stop .
   .It Ar file
   Read input from zero or more files.
   If unspecified, reads from stdin.
   If multiple files are specified,
   .Nm
 will halt with the first failed parse.  will halt with the first failed parse.
 .El  .El
 .\" PARAGRAPH  
 .Pp  .Pp
 By default,  By default,
 .Nm  .Nm
 reads  reads
 .Xr mdoc 7  .Xr mdoc 7
 or  or
 .Xr man 7  .Xr man 7
 text from stdin, implying  text from stdin, implying
 .Fl m Ns Ar andoc ,  .Fl m Ns Cm andoc ,
 and prints 78-column backspace-encoded output to stdout as if  and produces
 .Fl T Ns Ar ascii  .Fl T Ns Cm ascii
 were provided.  output.
 .\" PARAGRAPH  
 .Pp  
 .Ex -std mandoc  
 .\" SUB-SECTION  
 .Ss Punctuation  
 If punctuation is set apart from words, such as in the phrase  
 .Dq to be \&, or not to be ,  
 it's processed by  
 .Nm  
 according to the following rules.  Opening punctuation  
 .Po  
 .Sq \&( ,  
 .Sq \&[ ,  
 and  
 .Sq \&{  
 .Pc  
 is not followed by a space. Closing punctuation  
 .Po  
 .Sq \&. ,  
 .Sq \&, ,  
 .Sq \&; ,  
 .Sq \&: ,  
 .Sq \&? ,  
 .Sq \&! ,  
 .Sq \&) ,  
 .Sq \&]  
 and  
 .Sq \&}  
 .Pc  
 is not preceded by whitespace.  
 .Pp  
 If the input is  
 .Xr mdoc 7 ,  
 these rules are also applied to macro arguments when appropriate.  
 .\" SUB-SECTION  
 .Ss Input Formats  .Ss Input Formats
 The  The
 .Nm  .Nm
Line 137  utility accepts
Line 116  utility accepts
 and  and
 .Xr man 7  .Xr man 7
 input with  input with
 .Fl m Ns Ar doc  .Fl m Ns Cm doc
 and  and
 .Fl m Ns Ar an ,  .Fl m Ns Cm an ,
 respectively.  The  respectively.
   The
 .Xr mdoc 7  .Xr mdoc 7
 format is  format is
 .Em strongly  .Em strongly
 recommended;  recommended;
 .Xr man 7  .Xr man 7
 should only be used for legacy manuals.  should only be used for legacy manuals.
 .Pp  .Pp
 A third option,  A third option,
 .Fl m Ns Ar andoc ,  .Fl m Ns Cm andoc ,
 which is also the default, determines encoding on-the-fly: if the first  which is also the default, determines encoding on-the-fly: if the first
 non-comment macro is  non-comment macro is
 .Sq \&.Dd  .Sq \&Dd
 or  or
 .Sq \&.Dt ,  .Sq \&Dt ,
 the  the
 .Xr mdoc 7  .Xr mdoc 7
 parser is used; otherwise, the  parser is used; otherwise, the
 .Xr man 7  .Xr man 7
 parser is used.  parser is used.
 .Pp  .Pp
 If multiple  If multiple
 files are specified with  files are specified with
 .Fl m Ns Ar andoc ,  .Fl m Ns Cm andoc ,
 each has its file-type determined this way.  If multiple files are  each has its file-type determined this way.
   If multiple files are
 specified and  specified and
 .Fl m Ns Ar doc  .Fl m Ns Cm doc
 or  or
 .Fl m Ns Ar an  .Fl m Ns Cm an
 is specified, then this format is used exclusively.  is specified, then this format is used exclusively.
 .\" .Pp  
 .\" The following escape sequences are recognised, although the per-format  
 .\" compiler may not allow certain sequences.  
 .\" .Bl -tag -width Ds -offset XXXX  
 .\" .It \efX  
 .\" sets the font mode to X (B, I, R or P, where P resets the font)  
 .\" .It \eX, \e(XX, \e[XN]  
 .\" queries the special-character table for a corresponding symbol  
 .\" .It \e*X, \e*(XX, \e*[XN]  
 .\" deprecated special-character format  
 .\" .El  
 .\" SUB-SECTION  
 .Ss Output Formats  .Ss Output Formats
 The  The
 .Nm  .Nm
 utility accepts the following  utility accepts the following
 .Fl T  .Fl T
 arguments:  arguments, which correspond to output modes:
 .Bl -tag -width Ds  .Bl -tag -width "-Tlocale"
 .It Fl T Ns Ar ascii  .It Fl T Ns Cm ascii
 Produce 7-bit ASCII output, backspace-encoded for bold and underline  Produce 7-bit ASCII output.
 styles.  This is the default.  This is the default.
 .It Fl T Ns Ar tree  See
 Produce an indented parse tree.  .Sx ASCII Output .
 .It Fl T Ns Ar lint  .It Fl T Ns Cm html
   Produce strict CSS1/HTML-4.01 output.
   See
   .Sx HTML Output .
   .It Fl T Ns Cm lint
 Parse only: produce no output.  Parse only: produce no output.
   Implies
   .Fl W Ns Cm warning .
   .It Fl T Ns Cm locale
   Encode output using the current locale.
   See
   .Sx Locale Output .
   .It Fl T Ns Cm man
   Produce
   .Xr man 7
   format output.
   See
   .Sx Man Output .
   .It Fl T Ns Cm pdf
   Produce PDF output.
   See
   .Sx PDF Output .
   .It Fl T Ns Cm ps
   Produce PostScript output.
   See
   .Sx PostScript Output .
   .It Fl T Ns Cm tree
   Produce an indented parse tree.
   .It Fl T Ns Cm utf8
   Encode output in the UTF\-8 multi-byte format.
   See
   .Sx UTF\-8 Output .
   .It Fl T Ns Cm xhtml
   Produce strict CSS1/XHTML-1.0 output.
   See
   .Sx XHTML Output .
 .El  .El
 .Pp  .Pp
 If multiple input files are specified, these will be processed by the  If multiple input files are specified, these will be processed by the
 corresponding filter in-order.  corresponding filter in-order.
 .\" SUB-SECTION  .Ss ASCII Output
 .Ss Compiler Options  Output produced by
 Default compiler behaviour may be overriden with the  .Fl T Ns Cm ascii ,
 .Fl f  which is the default, is rendered in standard 7-bit ASCII documented in
 flag.  .Xr ascii 7 .
   .Pp
   Font styles are applied by using back-spaced encoding such that an
   underlined character
   .Sq c
   is rendered as
   .Sq _ Ns \e[bs] Ns c ,
   where
   .Sq \e[bs]
   is the back-space character number 8.
   Emboldened characters are rendered as
   .Sq c Ns \e[bs] Ns c .
   .Pp
   The special characters documented in
   .Xr mandoc_char 7
   are rendered best-effort in an ASCII equivalent.
   If no equivalent is found,
   .Sq \&?
   is used instead.
   .Pp
   Output width is limited to 78 visible columns unless literal input lines
   exceed this limit.
   .Pp
   The following
   .Fl O
   arguments are accepted:
 .Bl -tag -width Ds  .Bl -tag -width Ds
 .It Fl f Ns Ar ign-scope  .It Cm width Ns = Ns Ar width
 When rewinding the scope of a block macro, forces the compiler to ignore  The output width is set to
 scope violations.  This can seriously mangle the resulting tree.  .Ar width ,
 .Pq mdoc only  which will normalise to \(>=60.
 .It Fl f Ns Ar ign-escape  .El
 Ignore invalid escape sequences.  .Ss HTML Output
 .It Fl f Ns Ar ign-macro  Output produced by
 Ignore unknown macros at the start of input lines (default for  .Fl T Ns Cm html
   conforms to HTML-4.01 strict.
   .Pp
   The
   .Pa example.style.css
   file documents style-sheet classes available for customising output.
   If a style-sheet is not specified with
   .Fl O Ns Ar style ,
   .Fl T Ns Cm html
   defaults to simple output readable in any graphical or text-based web
   browser.
   .Pp
   Special characters are rendered in decimal-encoded UTF\-8.
   .Pp
   The following
   .Fl O
   arguments are accepted:
   .Bl -tag -width Ds
   .It Cm fragment
   Do not emit doctype, html, and body elements.
   The
   .Cm style
   argument shall be unused.
   This is useful when embedding manual content within existing documents.
   .It Cm includes Ns = Ns Ar fmt
   The string
   .Ar fmt ,
   for example,
   .Ar ../src/%I.html ,
   is used as a template for linked header files (usually via the
   .Sq \&In
   macro).
   Instances of
   .Sq \&%I
   are replaced with the include filename.
   The default is not to present a
   hyperlink.
   .It Cm man Ns = Ns Ar fmt
   The string
   .Ar fmt ,
   for example,
   .Ar ../html%S/%N.%S.html ,
   is used as a template for linked manuals (usually via the
   .Sq \&Xr
   macro).
   Instances of
   .Sq \&%N
   and
   .Sq %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.
   .It Cm style Ns = Ns Ar style.css
   The file
   .Ar style.css
   is used for an external style-sheet.
   This must be a valid absolute or
   relative URI.
   .El
   .Ss Locale Output
   Locale-depending output encoding is triggered with
   .Fl T Ns Cm locale .
   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
   .Fl T Ns Cm ascii .
   See
   .Sx ASCII Output
   for font style specification and available command-line arguments.
   .Ss Man Output
   Translate input format into
 .Xr man 7  .Xr man 7
 parsing).  output format.
 .It Fl f Ns Ar no-ign-macro  This is useful for distributing manual sources to legancy systems
 Do not ignore unknown macros at the start of input lines (default for  lacking
 .Xr mdoc 7  .Xr mdoc 7
 parsing).  formatters.
   .Pp
   If
   .Xr mdoc 7
   is passed as input, it is translated into
   .Xr man 7 ;
   if the input format is
   .Xr man 7 ,
   it is parsed and re-outputted.
   In either case, the
   .Xr roff 7
   .Sq so
   macros are processed prior to producing output.
   .Ss PDF Output
   PDF-1.1 output may be generated by
   .Fl T Ns Cm pdf .
   See
   .Sx PostScript Output
   for
   .Fl O
   arguments and defaults.
   .Ss PostScript Output
   PostScript
   .Qq Adobe-3.0
   Level-2 pages may be generated by
   .Fl T Ns Cm 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.
   .Pp
   Special characters are rendered as in
   .Sx ASCII Output .
   .Pp
   The following
   .Fl O
   arguments are accepted:
   .Bl -tag -width Ds
   .It Cm paper Ns = Ns Ar name
   The paper size
   .Ar name
   may be one of
   .Ar a3 ,
   .Ar a4 ,
   .Ar a5 ,
   .Ar legal ,
   or
   .Ar letter .
   You may also manually specify dimensions as
   .Ar NNxNN ,
   width by height in millimetres.
   If an unknown value is encountered,
   .Ar letter
   is used.
 .El  .El
 .\" PARAGRAPH  .Ss UTF\-8 Output
   Use
   .Fl T Ns Cm utf8
   to force a UTF\-8 locale.
   See
   .Sx Locale Output
   for details and options.
   .Ss XHTML Output
   Output produced by
   .Fl T Ns Cm xhtml
   conforms to XHTML-1.0 strict.
 .Pp  .Pp
 As with the  See
   .Sx HTML Output
   for details; beyond generating XHTML tags instead of HTML tags, these
   output modes are identical.
   .Sh EXIT STATUS
   The
   .Nm
   utility exits with one of the following values, controlled by the message
   .Ar level
   associated with the
 .Fl W  .Fl W
 flag, multiple  option:
 .Fl f  .Pp
 options may be grouped and delimited with a comma.  Using  .Bl -tag -width Ds -compact
 .Fl f Ns Ar ign-scope,ign-escape ,  .It 0
 for example, will try to ignore scope and character-escape errors.  No warnings or errors occurred, or those that did were ignored because
 .\" SECTION  they were lower than the requested
   .Ar level .
   .It 2
   At least one warning occurred, but no error, and
   .Fl W Ns Cm warning
   was specified.
   .It 3
   At least one parsing error occurred, but no fatal error, and
   .Fl W Ns Cm error
   or
   .Fl W Ns Cm warning
   was specified.
   .It 4
   A fatal parsing error occurred.
   .It 5
   Invalid command line arguments were specified.
   No input files have been read.
   .It 6
   An operating system error occurred, for example memory exhaustion or an
   error accessing input files.
   Such errors cause
   .Nm
   to exit at once, possibly in the middle of parsing or formatting a file.
   .El
   .Pp
   Note that selecting
   .Fl T Ns Cm lint
   output mode implies
   .Fl W Ns Cm warning .
 .Sh EXAMPLES  .Sh EXAMPLES
 To page manuals to the terminal:  To page manuals to the terminal:
 .\" PARAGRAPH  
 .Pp  .Pp
 .D1 % mandoc \-Wall,error mandoc.1 2>&1 | less  .Dl $ mandoc \-Wall,stop mandoc.1 2\*(Gt&1 | less
   .Dl $ mandoc mandoc.1 mdoc.3 mdoc.7 | less
 .Pp  .Pp
 .D1 % mandoc mandoc.1 mdoc.3 mdoc.7 | less  To produce HTML manuals with
 .\" SECTION  .Ar style.css
 .Sh SEE ALSO  as the style-sheet:
 .Xr mandoc_char 7 ,  .Pp
 .Xr mdoc 7 ,  .Dl $ mandoc \-Thtml -Ostyle=style.css mdoc.7 \*(Gt mdoc.7.html
   .Pp
   To check over a large set of manuals:
   .Pp
   .Dl $ mandoc \-Tlint `find /usr/src -name \e*\e.[1-9]`
   .Pp
   To produce a series of PostScript manuals for A4 paper:
   .Pp
   .Dl $ mandoc \-Tps \-Opaper=a4 mdoc.7 man.7 \*(Gt manuals.ps
   .Pp
   Convert a modern
   .Xr mdoc 7
   manual to the older
 .Xr man 7  .Xr man 7
 .\"  format, for use on systems lacking an
 .Sh AUTHORS  .Xr mdoc 7
 The  parser:
 .Nm  
 utility was written by  
 .An Kristaps Dzonsons Aq kristaps@kth.se .  
 .\" SECTION  
 .Sh CAVEATS  
 The  
 .Nm  
 utility in  
 .Fl T Ns Ar ascii  
 mode doesn't yet know how to display the following:  
 .Pp  .Pp
 .Bl -bullet -compact  .Dl $ mandoc \-Tman foo.mdoc \*(Gt foo.man
 .It  .Sh DIAGNOSTICS
 The \-hang  Standard error messages reporting parsing errors are prefixed by
 .Sq \&.Bl  .Pp
 list is not yet supported.  .Sm off
   .D1 Ar file : line : column : \ level :
   .Sm on
   .Pp
   where the fields have the following meanings:
   .Bl -tag -width "column"
   .It Ar file
   The name of the input file causing the message.
   .It Ar line
   The line number in that input file.
   Line numbering starts at 1.
   .It Ar column
   The column number in that input file.
   Column numbering starts at 1.
   If the issue is caused by a word, the column number usually
   points to the first character of the word.
   .It Ar level
   The message level, printed in capital letters.
 .El  .El
 .Pp  .Pp
 Other macros still aren't supported by virtue of nobody complaining  Message levels have the following meanings:
 about their absence.  Please report any omissions: this is a work in  .Bl -tag -width "warning"
 progress.  .It Cm fatal
   The parser is unable to parse a given input file at all.
   No formatted output is produced from that input file.
   .It Cm error
   An input file contains syntax that cannot be safely interpreted,
   either because it is invalid or because
   .Nm
   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 unintended formatting.
   .It Cm warning
   An input file uses obsolete, discouraged or non-portable syntax.
   All the same, the meaning of the input is unambiguous and a correct
   rendering can be produced.
   Documents causing warnings may render poorly when using other
   formatting tools instead of
   .Nm .
   .El
 .Pp  .Pp
 The following list documents differences between traditional  Messages of the
 .Xr nroff 1  .Cm warning
 output and  and
 .Nm :  .Cm error
   levels are hidden unless their level, or a lower level, is requested using a
   .Fl W
   option or
   .Fl T Ns Cm lint
   output mode.
 .Pp  .Pp
   The
   .Nm
   utility may also print messages related to invalid command line arguments
   or operating system errors, for example when memory is exhausted or
   input files cannot be read.
   Such messages do not carry the prefix described above.
   .Sh COMPATIBILITY
   This section summarises
   .Nm
   compatibility with GNU troff.
   Each input and output format is separately noted.
   .Ss ASCII Compatibility
 .Bl -bullet -compact  .Bl -bullet -compact
 .It  .It
 A list of display following  Unrenderable unicode codepoints specified with
 .Sq \&.Ss  .Sq \e[uNNNN]
   escapes are printed as
   .Sq \&?
   in mandoc.
   In GNU troff, these raise an error.
   .It
   The
   .Sq \&Bd \-literal
   and
   .Sq \&Bd \-unfilled
   macros of
   .Xr mdoc 7
   in
   .Fl T Ns Cm ascii
   are synonyms, as are \-filled and \-ragged.
   .It
   In historic GNU troff, the
   .Sq \&Pa
   .Xr mdoc 7
   macro does not underline when scoped under an
   .Sq \&It
   in the FILES section.
   This behaves correctly in
   .Nm .
   .It
   A list or display following the
   .Sq \&Ss
   .Xr mdoc 7
   macro in
   .Fl T Ns Cm ascii
 does not assert a prior vertical break, just as it doesn't with  does not assert a prior vertical break, just as it doesn't with
 .Sq \&.Sh .  .Sq \&Sh .
 .It  .It
 Special characters don't follow the current font style.  The
 .\" LIST-ITEM  .Sq \&na
   .Xr man 7
   macro in
   .Fl T Ns Cm ascii
   has no effect.
 .It  .It
 The \-literal and \-unfilled  Words aren't hyphenated.
 .Sq \&.Bd  
 displays types are synonyms, as are \-filled and \-ragged.  
 .El  .El
   .Ss HTML/XHTML Compatibility
   .Bl -bullet -compact
   .It
   The
   .Sq \efP
   escape will revert the font to the previous
   .Sq \ef
   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
   .Sx ASCII Output
   mode, this will work fine.
   .It
   The
   .Xr mdoc 7
   .Sq \&Bl \-hang
   and
   .Sq \&Bl \-tag
   list types render similarly (no break following overreached left-hand
   side) due to the expressive constraints of HTML.
   .It
   The
   .Xr man 7
   .Sq IP
   and
   .Sq TP
   lists render similarly.
   .El
   .Sh SEE ALSO
   .Xr eqn 7 ,
   .Xr man 7 ,
   .Xr mandoc_char 7 ,
   .Xr mdoc 7 ,
   .Xr roff 7 ,
   .Xr tbl 7
   .Sh AUTHORS
   The
   .Nm
   utility was written by
   .An Kristaps Dzonsons ,
   .Mt kristaps@bsd.lv .
   .Sh CAVEATS
   In
   .Fl T Ns Cm html
   and
   .Fl T Ns Cm xhtml ,
   the maximum size of an element attribute is determined by
   .Dv BUFSIZ ,
   which is usually 1024 bytes.
   Be aware of this when setting long link
   formats such as
   .Fl O Ns Cm style Ns = Ns Ar really/long/link .
   .Pp
   Nesting elements within next-line element scopes of
   .Fl m Ns Cm an ,
   such as
   .Sq br
   within an empty
   .Sq B ,
   will confuse
   .Fl T Ns Cm html
   and
   .Fl T Ns Cm xhtml
   and cause them to forget the formatting of the prior next-line scope.
   .Pp
   The
   .Sq \(aq
   control character is an alias for the standard macro control character
   and does not emit a line-break as stipulated in GNU troff.
Legend:
Removed from v.1.19  
changed lines
  Added in v.1.96
CVSweb