[Fontconfig] Cannot change DPI in ~/.fonts.conf for X applications?

[Pedro Ribeiro]

Hi all,

sorry for what might be a noob question. Only recently I discovered
the wonders of changing the DPI (I have poor eyesight for my high
resolution monitor).
I tried to change the DPI setting to something more acceptable (100 is
the ideal), but I cannot seem to be able to do it on ~/.fonts.conf. I
have there the correct setting:

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
 	<match target="font" >
  		<edit mode="assign" name="dpi" >
   			<double>100</double>
  		</edit>
 	</match>
</fontconfig>

However no application seems to take it seriously. But if I edit
~/.Xresources and add:

Xft.dpi:	100

the 100 DPI setting is enforced. Am I doing something wrong in
.fonts.conf or is this normal?

Regards,
Pedro