Provided by: mandoc_1.14.6-3_amd64 bug

NAME

     tbl — tbl language reference for mandoc

DESCRIPTION

     The tbl language formats tables.  It is used within mdoc(7) and man(7) pages.  This manual
     describes the subset of the tbl language accepted by the mandoc(1) utility.

     Each table is started with a roff(7) TS macro, consist of at most one line of Options, one
     or more Layout lines, one or more Data lines, and ends with a TE macro.  All input must be
     7-bit ASCII.

   Options
     If the first input line of a table ends with a semicolon, it contains case-insensitive
     options separated by spaces, tabs, or commas.  Otherwise, it is interpreted as the first
     Layout line.

     The following options are available.  Some of them require arguments enclosed in
     parentheses:

     allbox  Draw a single-line box around each table cell.

     box     Draw a single-line box around the table.  For GNU compatibility, this may also be
             invoked with frame.

     center  Center the table instead of left-adjusting it.  For GNU compatibility, this may also
             be invoked with centre.

     decimalpoint
             Use the single-character argument as the decimal point with the n layout key.  This
             is a GNU extension.

     delim   Use the two characters of the argument as eqn(7) delimiters.  Currently unsupported.

     doublebox
             Draw a double-line box around the table.  For GNU compatibility, this may also be
             invoked with doubleframe.

     expand  Increase the width of the table to the current line length.  Currently ignored.

     linesize
             Draw lines with the point size given by the unsigned integer argument.  Currently
             ignored.

     nokeep  Allow page breaks within the table.  This is a GNU extension and currently ignored.

     nospaces
             Ignore leading and trailing spaces in data cells.  This is a GNU extension.

     nowarn  Suppress warnings about tables exceeding the current line length.  This is a GNU
             extension and currently ignored.

     tab     Use the single-character argument as a delimiter between data cells.  By default,
             the horizontal tabulator character is used.

   Layout
     The table layout follows an Options line or a roff(7) TS or T& macro.  Each layout line
     specifies how one line of Data is formatted.  The last layout line ends with a full stop.
     It also applies to all remaining data lines.  Multiple layout lines can be joined by commas
     on a single physical input line.

     Each layout line consists of one or more layout cell specifications, optionally separated by
     whitespace.  The following case-insensitive key characters start a new cell specification:

     c   Center the string in this cell.

     r   Right-justify the string in this cell.

     l   Left-justify the string in this cell.

     n   Justify a number around its last decimal point.  If no decimal point is found in the
         number, it is assumed to trail the number.

     s   Horizontally span columns from the last non-s layout cell.  It is an error if a column
         span follows a _ or = cell, or comes first on a layout line.  The combined cell as a
         whole consumes only one cell of the corresponding data line.

     a   Left-justify a string and pad with one space.

     ^   Vertically span rows from the last non-^ layout cell.  It is an error to invoke a
         vertical span on the first layout line.  Unlike a horizontal span, a vertical span
         consumes a data cell and discards the content.

     _   Draw a single horizontal line in this cell.  This consumes a data cell and discards the
         content.  It may also be invoked with -.

     =   Draw a double horizontal line in this cell.  This consumes a data cell and discards the
         content.

     Each cell key may be followed by zero or more of the following case-insensitive modifiers:

     b   Use a bold font for the contents of this cell.

     d   Move content down to the last row of this vertical span.  Currently ignored.

     e   Make this column wider to match the maximum width of any other column also having the e
         modifier.

     f   The next one or two characters select the font to use for this cell.  One-character font
         names must be followed by a blank or period.  See the roff(7) manual for supported font
         names.

     i   Use an italic font for the contents of this cell.

     m   Specify a cell start macro.  This is a GNU extension and currently unsupported.

     p   Set the point size to the following unsigned argument, or change it by the following
         signed argument.  Currently ignored.

     v   Set the vertical line spacing to the following unsigned argument, or change it by the
         following signed argument.  Currently ignored.

     t   Do not vertically center content in this vertical span, leave it in the top row.
         Currently ignored.

     u   Move cell content up by half a table row.  Currently ignored.

     w   Specify a minimum column width.

     x   After determining the width of all other columns, distribute the rest of the line length
         among all columns having the x modifier.

     z   Do not use this cell for determining the width of this column.

     |   Draw a single vertical line to the right of this cell.

     ||  Draw a double vertical line to the right of this cell.

     If a modifier consists of decimal digits, it specifies a minimum spacing in units of n
     between this column and the next column to the right.  The default is 3.  If there is a
     vertical line, it is drawn inside the spacing.

   Data
     The data section follows the last Layout line.  Each data line consists of one or more data
     cells, delimited by tab characters.

     If a data cell contains only the two bytes ‘\^’, the cell above spans to this row, as if the
     layout specification of this cell were ^.

     If a data cell contains only the single character ‘_’ or ‘=’, a single or double horizontal
     line is drawn across the cell, joining its neighbours.  If a data cell contains only the two
     character sequence ‘\_’ or ‘\=’, a single or double horizontal line is drawn inside the
     cell, not joining its neighbours.  If a data line contains nothing but the single character
     ‘_’ or ‘=’, a horizontal line across the whole table is inserted without consuming a layout
     row.

     In place of any data cell, a text block can be used.  It starts with T{ at the end of a
     physical input line.  Input line breaks inside the text block neither end the text block nor
     its data cell.  It only ends if T} occurs at the beginning of a physical input line and is
     followed by an end-of-cell indicator.  If the T} is followed by the end of the physical
     input line, the text block, the data cell, and the data line ends at this point.  If the T}
     is followed by the tab character, only the text block and the data cell end, but the data
     line continues with the data cell following the tab character.  If T} is followed by any
     other character, it does not end the text block, which instead continues to the following
     physical input line.

EXAMPLES

     String justification and font selection:

           .TS
           rb c  lb
           r  ci l.
           r       center  l
           ri      ce      le
           right   c       left
           .TE

               r   center   l
              ri     ce     le
           right     c      left

     Some ports in OpenBSD 6.1 to show number alignment and line drawing:

           .TS
           box tab(:);
           r| l
           r  n.
           software:version
           _
           AFL:2.39b
           Mutt:1.8.0
           Ruby:1.8.7.374
           TeX Live:2015
           .TE

           ┌─────────┬───────────┐
           │software │ version   │
           ├─────────┴───────────┤
           │     AFL       2.39b │
           │    Mutt     1.8.0   │
           │    Ruby   1.8.7.374 │
           │TeX Live    2015     │
           └─────────────────────┘

     Spans and skipping width calculations:

           .TS
           box tab(:);
           lz  s | rt
           lt| cb| ^
           ^ | rz  s.
           left:r
           l:center:
           :right
           .TE

           ┌───────────┬───┐
--

COMPATIBILITY

     The mandoc(1) implementation of tbl doesn't support mdoc(7) and man(7) macros and eqn(7)
     equations inside tables.

SEE ALSO

     mandoc(1), man(7), mandoc_char(7), mdoc(7), roff(7)

     M. E. Lesk, Tbl  A Program to Format Tables, June 11, 1976.

HISTORY

     The tbl utility, a preprocessor for troff, was originally written by M.  E. Lesk at Bell
     Labs in 1975.  The GNU reimplementation of tbl, part of the groff package, was released in
     1990 by James Clark.  A standalone tbl implementation was written by Kristaps Dzonsons in
     2010.  This formed the basis of the implementation that first appeared in OpenBSD 4.9 as a
     part of the mandoc(1) utility.

AUTHORS

     This tbl reference was written by Kristaps Dzonsons <kristaps@bsd.lv> and
     Ingo Schwarze <schwarze@openbsd.org>.

BUGS

     In -T utf8 output mode, heavy lines are drawn instead of double lines.  This cannot be
     improved because the Unicode standard only provides an incomplete set of box drawing
     characters with double lines, whereas it provides a full set of box drawing characters with
     heavy lines.  It is unlikely this can be improved in the future because the box drawing
     characters are already marked in Unicode as characters intended only for backward
     compatibility with legacy systems, and their use is not encouraged.  So it seems unlikely
     that the missing ones might get added in the future.