[Denemo-devel] PNG selection export (was Re: Beginner questions (cross-staff, PNG selection export, feathered beams, batch export, Print View behaviour))

[Richard Shann]

On Tue, 2019-08-13 at 10:56 +0200, Lib Lists wrote:
> > > Hi, writing in a terminal '/PATH/TO/Preview somefile.png' doesn't
> > > work. However, 'open -a  /PATH/TO/Preview somefile.png' works as
> > > well
> > > as 'open somefile.png'.
> > 
> > In that case you may be able to set the Image Viewer field to
> > "open"
> > without the quotes
> > and it may work. (I'm hoping there is an executable named "open"
> > that
> > takes a filename as a parameter and decides what to do with it)
> > 
> 
> Hi, I tried but it doesn't work, same result as before. I tried
> 'open', 'open -a PATH/TO/Preview'. Here the
> man page for 'open'
> https://ss64.com/osx/open.html. In the preferences I also setup an
> internet browser ('PATH/TO/Safari) and I found a problem: Safari
> correctly opens, but the address to the file (the help file in this
> case) is written as:
> file:///file:/Applications/Denemo.app/Contents/Resources/share/denemo
> /manual/denemo-manual.html
> with the double 'file' bit at the beginning. Maybe related with the
> problem with Preview?

Well, this sounds like it is not difficult to fix: Denemo is
successfully launching the executable program, but the programs
launched are failing to pick up and use the parameter appropriately. In
the case of Safari it is taking the parameter to be a file name and
prefixing file:/// to it while how the "open" thing is failing is less
clear, as the man page you quote indicates that calling it with a pdf
filename as parameter should work. Setting the field to 'open -a
PATH/TO/Preview' would *not* work, as it would try to execute a program
named 'open -a PATH/TO/Preview' which doesn't exist.
So the easy fix is to create a script that calls the program you want
to call with the correct parameter. On Unix you would write a file
containing something like

8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><
#!/bin/bash

echo Opening $1 as png using the command: open -a /PATH/TO/Preview $1

open -a /PATH/TO/Preview $1

8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><8><

you would put this into a file, say myopen.sh and make it executable
chmod a+x myopen.sh

You could use any other scripting language to take the file name as
provided by Denemo and invoke your display program.

However, it sounds like "open" may not behave like a normal executable
program, and a quick search for Preview on the MacOS suggests that you
cannot invoke it with an option to provide the filename that Preview is
to work on - is there a man page for Preview? - so if that is really
the case, bizarre as it seems, then you might have to write an
AppleScript or use some more normal display program.

HTH

Richard