[Groff] PostScript in groff

[Miklos Somogyi]

In my previous post re this subject I wrote that the \X'ps: file ...' 
scheme uploaded the named PS file
into the final PS form of the document verbatim.
Unfortunately this is not true.

I stated this because I was only looking at passing parameters, 
contents of number registers and strings
to PS and `trf' supports these, but the `file' construct does not look 
for backslashes.
However, as I just found it out, it does look for something else.

Ascii85 encoding of image files is like having your cake and eat it: it 
is much smaller than asciihex, and it is still ascii.
It maps image data into the [!...u] character range, and that contains 
\ and %.
Because of the backslashes such a file can not be read-in via `trf', 
but I thought that `file' would be ok.

Unfortunately this one looks for `%!' and does not copy lines starting 
with these two characters.
Since you can not exclude the possibility of such a combination, 
ascii85 encoded files are out.

Miklos