Re: [PATCH] lint-man.mk: Use a pipeline instead of the groff(1) wrapper

[Alejandro Colomar]

Hi Ralph, Branden,

On 8/28/22 13:20, Alejandro Colomar wrote:
> Hi Ralph,
>
> On 8/28/22 10:36, Ralph Corderoy wrote:
> > Hi Alejandro,
> >
> > > +DEFAULT_EQNFLAGS := -Tutf8
> > ...
> > > +DEFAULT_TROFFFLAGS   += -Tutf8
> >
> > I'd have a variable set to ‘utf8’ to ease changing to another output
> > device.
>
> Done; thanks!  And as I said in another thread, I changed it back to 
> ascii, since I noticed a problem with boxed tables (actually several).
>
> I noticed another issue: for some reason, the boxed tables are being 
> generated wider than the terminal, exactly by one char.  If I specify 
> -rLL=80, the right edge of the box is placed at column 81; if I specify 
> LL to be 72, the right edge of the box is at col 73.
>
> See the example below (I tweaked it to use 64 chars to overcome 
> Thunderbird issues):
>
>
> $ tbl man3/err.3 \
>    | eqn -Tascii \
>    | troff -man -t -M ./etc/groff/tmac -m checkstyle -rCHECKSTYLE=3 \
>            -ww -Tascii -rLL=64n \
>    | grotty -c \
>    | col -b -x \
>    | (! grep -n '.\{64\}.')
> 21:       noreturn void verr(int eval, const char *fmt, va_list args);
> 22:       noreturn void verrx(int eval, const char *fmt, va_list args);
> 51:       +-----------------------+---------------+----------------+
> 52:       |Interface              | Attribute     | Value          |
> 53:       +-----------------------+---------------+----------------+
> 54:       |err(), errx(), warn(), | Thread safety | MT-Safe locale |
> 55:       |warnx(), verr(),       |               |                |
> 56:       |verrx(), vwarn(),      |               |                |
> 57:       |vwarnx()               |               |                |
> 58:       +-----------------------+---------------+----------------+
>
>
> Do you know how I can fix that?

Hmmm, I've been testing things, and groff -rLL=78 behaves as MANWIDTH=80 
man.  That's weird.  We come back to this 78 issue we didn't know 
exactly why it was there.

Searching through man-db's source code, it seems to confirm that 
subtraction:

alx@asus5775:~/src/cjwatson/man-db$ grepc get_line_length
./lib/linelength.h:23:
int get_line_length (void);


./lib/linelength.c:49:
int get_line_length (void)
{
        const char *columns;
        int width;
#ifdef TIOCGWINSZ
        int dev_tty, tty_fd = -1;
#endif

        if (line_length != -1)
                return line_length;

        line_length = 80;

        columns = getenv ("MANWIDTH");
        if (columns != NULL) {
                width = atoi (columns);
                if (width > 0)
                        return line_length = width;
        }

        [...]
}

alx@asus5775:~/src/cjwatson/man-db$ grepc get_roff_line_length
./src/man.c:651:
static int get_roff_line_length (void)
{
        int line_length = cat_width ? cat_width : get_line_length ();

        /* groff >= 1.18 defaults to 78. */
        if ((!troff || ditroff) && line_length != 80) {
                int length = line_length * 39 / 40;
                if (length > line_length - 2)
                        return line_length - 2;
                else
                        return length;
        } else
                return 0;
}


Cheers,

Alex

--
Alejandro Colomar
<http://www.alejandro-colomar.es/>

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