Provided by: groff_1.23.0-3build2_amd64 bug

Name

       grohtml, post-grohtml, pre-grohtml - groff output driver for HTML

Synopsis

       pre-grohtml [-epV] [-a anti-aliasing-text-bits] [-D image-directory] [-F font-directory]
                   [-g anti-aliasing-graphic-bits] [-i resolution] [-I image-stem] [-o image-
                   vertical-offset] [-x html-dialect] troff-command troff-argument ...

       pre-grohtml --help

       pre-grohtml -v
       pre-grohtml --version

       post-grohtml [-bCGhlnrVy] [-F font-directory] [-j output-stem] [-s base-point-size] [-S
                    heading-level] [-x html-dialect] [file ...]

       post-grohtml --help

       post-grohtml -v
       post-grohtml --version

Description

       The GNU roff system's HTML support consists of a preprocessor, pre-grohtml, and an  output
       driver,  post-grohtml;  together,  they  translate  roff(7)  documents to HTML.  Because a
       preprocessor is (uniquely) required for this output driver, users  should  invoke  grohtml
       via the groff(1) command with the -Thtml or -Txhtml options.  (In this installation, ps is
       the default output device.)  Use groff's -P option to pass  any  options  shown  above  to
       grohtml.   If  no  operands are given, or if file is “-”, grohtml reads the standard input
       stream.  Output is written to the standard output stream.

       grohtml invokes groff twice.  In the first  pass,  the  preprocessor  pre-grohtml  renders
       pictures, equations, and tables as images in PostScript format using the ps output device.
       In the second pass, the output driver post-grohtml translates the output  of  troff(1)  to
       HTML.

       grohtml  writes  output  encoded  in  UTF-8  and  has  built-in HTML entities for all non-
       composite Unicode characters.  In spite of this, groff may issue  warnings  about  unknown
       special  characters  if  they  can't be found during the first pass.  Such warnings can be
       safely ignored unless the special characters appear inside a table or equation.

   Typefaces
       grohtml supports the standard four styles: R (roman), I (italic), B (bold), and BI  (bold-
       italic).  Fonts are grouped into families T and C having members in each style.

              TR     Times roman
              TI     Times italic
              TB     Times bold
              TBI    Times bold-italic
              CR     Courier roman
              CI     Courier italic
              CB     Courier bold
              CBI    Courier bold-italic

       A special font, S, is also provided to accommodate roff documents that expect it to always
       be available.

   Font description files
       The font description files used with grohtml expose the same  glyph  repertoire  in  their
       charset sections.  See groff_font(5).

   Dependencies
       pre-grohtml  generates  an  image  whenever  an eqn equation, tbl table, or pic picture is
       encountered in the input.  grohtml therefore may run  several  commands  as  part  of  its
       operation.   These  include  the  Netpbm  tools pnmcrop, pnmcut, and pnmtopng; Ghostscript
       (gs); and the PSUtils tool psselect.

Options

       --help displays a usage message, while -v and --version show version information; all exit
       afterward.

       -a anti-aliasing-text-bits
              Number  of  bits of antialiasing information to be used by text when generating PNG
              images.  The default is 4 but 0, 1, and 2 are also valid.  Your system's version of
              gs  must  support  the  -dTextAlphaBits option in order to exploit antialiasing.  A
              value of 0 stops grohtml from issuing antialiasing commands to gs.

       -b     Initialize the background color to white.

       -C     Suppress output of “CreationDate:” HTML comment.

       -D image-directory
              Instruct grohtml to place all image files into directory image-directory.

       -e     Direct eqn to produce MathML.

              This option should not be manually specified; it is synthesized by groff  depending
              on whether it was given the -Thtml or -Txhtml option.

       -F font-directory
              Prepend  directory  font-directory/devname  to  the search path for font and device
              description files; name is the name of the device, usually html.

       -g anti-aliasing-graphic-bits
              Number of bits of antialiasing information to be used by graphics  when  generating
              PNG  images.   The  default  is  4  but  0, 1, and 2 are also valid.  Your system's
              version of gs must support  the  -dGraphicAlphaBits  option  in  order  to  exploit
              antialiasing.  A value of 0 stops grohtml from issuing antialiasing commands to gs.

       -G     Suppress output of “Creator:” HTML comment.

       -h     Generate  section  headings  by using HTML B elements and increasing the font size,
              rather than HTML H elements.

       -i resolution
              Set the image resolution in pixels per inch; the default is 100.

       -I image-stem
              Determine the image file name stem.  If omitted, grohtml uses grohtml-XXXXX  (where
              XXXXX  is  the process ID).  A dash is appended to the stem to separate it from the
              following image number.

       -j output-stem
              Instruct grohtml to split the HTML output into multiple files.  Output  is  written
              to  a  new  file  at  each  section heading (but see option -S below) named output-
              stem-n.html.

       -l     Turn off the production of automatic section links at the top of the document.

       -n     Generate simple  heading  anchors  whenever  a  section/number  heading  is  found.
              Without  the  option  the  anchor  value  is  the  textual heading.  This can cause
              problems when a heading contains a “?” on older versions of  some  browsers.   This
              feature is automatically enabled if a heading contains an image.

       -o image-vertical-offset
              Specify the vertical offset of images in points.

       -p     Display  page  rendering progress to the standard error stream.  grohtml displays a
              page number only when an image is required.

       -r     Turn off the automatic header and footer line (HTML rule).

       -s base-type-size
              Set the document's base type size in points.  When this size is used in the source,
              it  corresponds  to  the  HTML base type size.  Every increase of two points in the
              source will produce a “big” element, and conversely when a decrease of  two  points
              is seen, a “small” element is emitted.

       -S heading-level
              When  splitting  HTML  output  (see  option -j above), split at each nested heading
              level defined by heading-level, or higher).  The default is 1.

       -V     Create an XHTML or HTML validator  button  at  the  bottom  of  each  page  of  the
              document.

       -x html-dialect
              Select  HTML  dialect.  Currently, html-dialect should be either the digit 4 or the
              letter x, which  indicates  whether  grohtml  should  generate  HTML  4  or  XHTML,
              respectively.

              This  option should not be manually specified; it is synthesized by groff depending
              on whether it was given the -Thtml or -Txhtml option.

       -y     Produce a right-aligned groff signature at the end of the document (only if  -V  is
              also specified).

Environment

       GROFF_FONT_PATH
              lists directories in which to search for devhtml, grohtml's directory of device and
              font description files.  See troff(1) and groff_font(5).

       SOURCE_DATE_EPOCH
              A timestamp (expressed as seconds since the  Unix  epoch)  to  use  as  the  output
              creation  timestamp  in place of the current time.  The time is converted to human-
              readable form using gmtime(3) and asctime(3), and recorded in an HTML comment.

       TZ     The time zone to use when converting the current time to human-readable  form;  see
              tzset(3).   If  SOURCE_DATE_EPOCH is used, it is always converted to human-readable
              form using UTC.

Files

       /usr/share/groff/1.23.0/font/devhtml/DESC
              describes the html output device.

       /usr/share/groff/1.23.0/font/devhtml/F
              describes the font known as F on device html.

       /usr/share/groff/1.23.0/tmac/html.tmac
              defines font mappings, special characters, and colors for use with the html  output
              device.   It  is  automatically  loaded by troffrc when either of the html or xhtml
              output devices is selected.

       /usr/share/groff/1.23.0/tmac/html-end.tmac
              finalizes setup  of  the  html  output  device.   It  is  automatically  loaded  by
              troffrc-end when either of the html or xhtml output devices is selected.

       grohtml  uses  temporary  files.   See  groff(1)  for  details  about where such files are
       created.

Bugs

       grohtml is still beta code.

       grohtml does not truly support hyphenation, but you can  fool  it  into  hyphenating  long
       input  lines,  which  can appear in HTML output with a hyphenated word followed by a space
       but no line break.

See also

       groff(1), troff(1), groff_font(5)