我创建了一个包含postrm删除用户的脚本的包。运行时sudo apt-get remove ...，该postrm脚本的行为符合预期：
vagrant@vagrant-ubuntu-trusty-64:~$ sudo apt-get -y remove datim4u-auto-cert-updater
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
datim4u-auto-cert-updater
0 upgraded, 0 newly installed, 1 to remove and 32 not upgraded.
After this operation, 18.4 kB disk space will be freed.
(Reading database ... 70225 files and directories currently installed.)
Removing datim4u-auto-cert-updater (1.0.1~trusty) ...
Removing user datim4u_auto_cert_updater and its home directory...
Looking for files to backup/remove ...
Removing files ...
Removing user `datim4u_auto_cert_updater' ...
Warning: group `datim4u_auto_cert_updater' has no more members.
Done.
但是，在运行时sudo apt-get purge ...，postrm脚本运行了两次，导致错误/usr/sbin/deluser: The user '...' does not exist.：
vagrant@vagrant-ubuntu-trusty-64:~$ sudo apt-get -y purge datim4u-auto-cert-updater
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
datim4u-auto-cert-updater*
0 upgraded, 0 newly installed, 1 to remove and 32 not upgraded.
After this operation, 18.4 kB disk space will be freed.
(Reading database ... 70225 files and directories currently installed.)
Removing datim4u-auto-cert-updater (1.0.1~trusty) ...
Removing user datim4u_auto_cert_updater and its home directory...
Looking for files to backup/remove ...
Removing files ...
Removing user `datim4u_auto_cert_updater' ...
Warning: group `datim4u_auto_cert_updater' has no more members.
Done.
Purging configuration files for datim4u-auto-cert-updater (1.0.1~trusty) ...
Removing user datim4u_auto_cert_updater and its home directory...
/usr/sbin/deluser: The user `datim4u_auto_cert_updater' does not exist.
答案1
这是意料之中的，也是正常的。维护者脚本可能在包配置期间被多次调用，并且它们被调用时带有一个参数，指示它们被调用的操作。你可以在Debian Wiki 页面中的维护者脚本，包括此流程图移除和清除（与首先删除然后在不同操作中清除的包相反）：
全部您的维护脚本（{pre,post}{inst,rm}）应该注意传递给它们的参数并采取相应的行动。