Bug#881805: /usr/bin/xset: [xset] "xset +fp unix/:7101" doesn't work

[boffi <giacomo.boffi@gmail.com>]

Package: x11-xserver-utils
Version: 7.7+7+b1
Severity: normal
File: /usr/bin/xset

Dear Maintainer,

I wish to be able to use TTF fonts with ancient X programs that understand only
XLFD, so I installed the packages "xfstt" and "x11-xfs-utils".

Firstly I verified that the font server was running

    $ xfsinfo -server unix/:7101
    name of server: unix/:7101
    version number: 2
    vendor string:  HD
    vendor release number:  1
    maximum request size:   1024 longwords (8192 bytes)
    number of catalogues:   0
    Number of alternate servers: 0
    number of extensions:   0
 
next I verified that the font server knew about (at least some of) my
ttf fonts

    $ fslsfonts -server unix/:7101
    ...
    -ttf-bitstream-vera-bitstream vera sans mono-medium-r-normal-roman-0-0-0-0-m-0-iso8859-1
    ...

and eventually I tried to add the fonts served on "unix/:7101" using the
syntax that is documented in every place

    $ xset +fp unix/:7101
    xset:  bad font path element (#0), possible causes are:
        Directory does not exist or has wrong permissions
        Directory missing fonts.dir
        Incorrect font server address or syntax

so I have a running font server but no way of using it.

I know that I could use /etc/X11/Xconfig (?) but my system works w/o such a file
and I'd prefer to use the xset alternative because I fear to introduce new problems.

Thank you in advance for your attention,
                                                                         gb

-- System Information:
Debian Release: buster/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.13.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE=C.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages x11-xserver-utils depends on:
ii  cpp          4:7.2.0-1d1
ii  libc6        2.24-17
ii  libice6      2:1.0.9-2
ii  libx11-6     2:1.6.4-3
ii  libxaw7      2:1.0.13-1+b2
ii  libxcursor1  1:1.1.14-3
ii  libxext6     2:1.3.3-1+b2
ii  libxi6       2:1.7.9-1
ii  libxmu6      2:1.1.2-2
ii  libxmuu1     2:1.1.2-2
ii  libxrandr2   2:1.5.1-1
ii  libxrender1  1:0.9.10-1
ii  libxt6       1:1.1.5-1
ii  libxxf86vm1  1:1.1.4-1+b2

x11-xserver-utils recommends no packages.

Versions of packages x11-xserver-utils suggests:
pn  cairo-5c        <none>
pn  nickle          <none>
ii  xorg-docs-core  1:1.7.1-1.1

-- no debconf information