Re: Multiline Subject as PDF metadata

[Deri]

On Tuesday, 25 January 2022 19:18:58 GMT Tadziu Hoffmann wrote:
> > This metadata is held in the "document information dictionary"
> > of the pdf. In the pdf 1.4 standard the items
> > Title/Author/Keywords/Subject are all defined as text strings,
> > so I believe that precludes them from being multiline.
> 
> You can embed \n into the strings, but not all programs will
> display this as a newline -- pdfinfo does, but my version of
> acroread displays a boxed "000A" instead.
> 
>   \X'ps: exec mark \
>   /Title (\\nMy\\nmultiline\\ndocument\\ntitle\\n) \
>   /Synopsis (A short description of the document content.) \
>   /CreationDate (Jan 25, 2022) \
>   /ModDate (Jan 25, 2022) \
>   /DOCINFO pdfmark'
>   Hello, world!
> 
> I used groff -Tps and ps2pdf to create the PDF file,


This works:-

.sp 1i
.pdfinfo /Title "\[u000a]My\[u000a]multiline\[u000a]document\[u000a]title\
[u000a]"
.pdfinfo /Synopsis "A short description of the document content."
Hello, world!

BUT, you will need a small tweak to the program gropdf. This patch should 
allow multi-line .pdfinfo using \[u000a] as the line separator and -Tpdf:-

--- a/src/devices/gropdf/gropdf.pl
+++ b/src/devices/gropdf/gropdf.pl
@@ -876,9 +876,9 @@ sub do_x
                $pdfmark=~s((\d{4,6}) u)(sprintf("%.1f",$1/
$desc{sizescale}))eg;
                $pdfmark=~s(\\\[u00(..)\])(chr(hex($1)))eg;
 
-               if ($pdfmark=~m/(.+) \/DOCINFO\s*$/)
+               if ($pdfmark=~m/(.+) \/DOCINFO\s*$/s)
                {
-                   my @xwds=split(' ',"<< $1 >>");
+                   my @xwds=split(/ /,"<< $1 >>");
                    my $docinfo=ParsePDFValue(\@xwds);
 
                    foreach my $k (sort keys %{$docinfo})

I will soon be adding this patch to groff git.

Cheers 

Deri