demo RPM that changes permissions on a system folder
Created as part of investigation of issues with permissions on /var/tmp being repeatedly broken. We eventually realised that this happened after installation of a set of packages (which we do regularly as part of testing).
CentOS 5.x will silently change the permissions. An rpm built from the same spec file on CentOS 7.x won't install without --force.
[vagrant@localhost paul1]$ sudo rpm -i ~/rpmbuild/RPMS/x86_64/var_tmp-1.0-1.x86_64.rpm
file /var/tmp from install of var_tmp-1.0-1.x86_64 conflicts with file from package filesystem-3.2-21.el7.x86_64
[vagrant@localhost paul1]$ rpm -q var_tmp
package var_tmp is not installed
[vagrant@localhost paul1]$ ls -ld /var/tmp
drwxrwxrwt. 7 root root 4096 Jun 15 14:39 /var/tmp
[vagrant@localhost paul1]$ sudo rpm -i ~/rpmbuild/RPMS/x86_64/var_tmp-1.0-1.x86_64.rpm --force
[vagrant@localhost paul1]$ ls -ld /var/tmp
drwxrwx---. 7 root root 4096 Jun 15 14:39 /var/tmp
[vagrant@localhost var_tmp_rpm]$ rpm -qlvp ~/rpmbuild/RPMS/x86_64/var_tmp-1.0-1.x86_64.rpm
drwxrwx--- 2 root root 0 Jun 15 14:58 /var/tmp
[vagrant@localhost var_tmp_rpm]$ sudo rpm -i ~/rpmbuild/RPMS/x86_64/var_tmp-1.0-1.x86_64.rpm
[vagrant@localhost var_tmp_rpm]$ ls -ld /var/tmp
drwxrwx---. 2 root root 4096 Jun 15 14:58 /var/tmp
[vagrant@localhost var_tmp_rpm]$ rpm -q var_tmp
var_tmp-1.0-1.x86_64
[vagrant@localhost var_tmp_rpm]$ rpm -qf /var/tmp
filesystem-2.4.30-3.el6.x86_64
var_tmp-1.0-1.x86_64
[vagrant@localhost ~]$ sudo rpm -i ~/rpmbuild/RPMS/x86_64/var_tmp-1.0-1.x86_64.rpm
[vagrant@localhost ~]$ ls -dl /var/tmp
drwxrwx--- 5 root root 4096 Jun 15 14:29 /var/tmp