How to configure font size for Qt4 applications?

[Duncan]

Nikos Chantziaras posted on Tue, 04 Apr 2017 17:44:52 +0300 as excerpted:

> When running Qt4 applications (there's still quite a few of them), they
> use a very tiny font for their UI. When I run the "qtconfig" tool to
> configure the font size, it works initially. However, on the next login,
> KDE overwrites my ~/.config/Trolltech.conf file and puts this in it:
> 
>    font="Sans Serif,9,-1,5,50,0,0,0,0,0"
> 
> So all Qt4 apps use a 9pt font again, which for me is tiny.
> 
> I cannot find a spot in System Settings where that "9" comes from
> though.

I can't answer your question directly, but back in the qt4/kde4 era, I 
had to prevent overwrites of a number of files by setting them read-only.

Tho note that setting the file read-only will /often/ but not always 
work, because if the directory is still writable, some apps will replace 
the file.

There's at least two ways around that (assuming you can't just set the 
dir read-only as well), one being setting the file to immutable, tho of 
course that requires a filesystem that supports the immutable attribute.  
(Ext* does and btrfs does, but AFAIK reiserfs, which I used for years and 
still use on my non-ssd devices, doesn't.)

Another is a bind-mount of the file over itself (bind-mounts can be 
scoped to a single file if desired, or a dir or full filesystem, of 
course), read-only, and any other standard mount option you want to 
enforce (nodev, noexec, etc).  I've been doing that with my named/bind 
chroot for years (security reasons), bind-mounting various bits into it 
noexec, etc, using an fstab line.  Back before systemd I had to put noauto 
in fstab options and actually mount in an initscript that ran after the 
main filesystems were loaded (in the named initscript itself in my case), 
but systemd apparently detects that sort of mount-order dependency 
automatically and "just worked" without noauto in the bind-mount fstab 
options, so it mounted along with the other at-boot filesystems, but 
ordered after the main filesystems I was bind-mounting.

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman