Bug#974751: guix: Fails to install with "guix.postinst: 5: systemd-sysusers: not found" if package systemd is not installed

[Axel Beckert]

Package: guix
Version: 1.2.0~rc1-1
Severity: serious

Dear Vagrant,

your recently uploaded guix package fails in the postinst script as
follows on a system without the package systemd being installed:

Setting up guix (1.2.0~rc1-1) ...
/var/lib/dpkg/info/guix.postinst: 5: systemd-sysusers: not found
dpkg: error processing package guix (--configure):
 installed guix package post-installation script subprocess returned error exit status 127

Please try to guard that call (and/or provide an alternative code path)
so that it also works with other init systems or even completely without
an init system (like in a chroot).

If that's not possible, you probably need to add a dependency on
"systemd | opensysusers" and check for "sysusers" or "opensysusers"
instead of systemd-sysusers, too. opensysusers is an alternative
implementation of systemd's sysusers that also works with other init
systems or without init system at all.

-- System Information:
Debian Release: bullseye/sid
  APT prefers unstable
  APT policy: (990, 'unstable'), (600, 'testing'), (500, 'unstable-debug'), (500, 'buildd-unstable'), (110, 'experimental'), (1, 'experimental-debug'), (1, 'buildd-experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 5.7.0-2-amd64 (SMP w/4 CPU threads)
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /bin/dash
Init: sysvinit (via /sbin/init)
LSM: AppArmor: enabled

Versions of packages guix depends on:
ii  guile-3.0                        3.0.4-3
ii  guile-3.0-libs                   3.0.4-3
ii  guile-gcrypt                     0.3.0-2
ii  guile-git                        0.4.0-1
ii  guile-gnutls                     3.6.15-5
ii  guile-json                       4.3.2-2
ii  guile-lzlib                      0.0.2-2
ii  guile-sqlite3                    0.1.3-1
ii  guile-ssh                        0.13.1-3
ii  guile-zlib                       0.0.1-3
ii  libbz2-1.0                       1.0.8-4
ii  libc6                            2.31-4
ii  libgcc-s1                        10.2.0-17
ii  libgcrypt20                      1.8.7-2
ii  libgcrypt20-dev [libgcrypt-dev]  1.8.7-2
ii  libgit2-dev                      1.0.1+dfsg.1-1
ii  libsqlite3-0                     3.33.0-1
ii  libsqlite3-dev                   3.33.0-1
ii  libssh-dev                       0.9.4-2
ii  libstdc++6                       10.2.0-17
ii  zlib1g                           1:1.2.11.dfsg-2

Versions of packages guix recommends:
pn  nscd  <none>

guix suggests no packages.

-- no debconf information