find /var/log/* | xargs file
/var/log/apt:                                                  directory
/var/log/auth.log:                                             ASCII text, with very long lines
/var/log/btmp:                                                 empty
/var/log/dist-upgrade:                                         directory
/var/log/dmesg:                                                ASCII text
/var/log/dpkg.log:                                             ASCII text
/var/log/faillog:                                              data
/var/log/fsck:                                                 directory
/var/log/fsck/checkroot:                                       ASCII text
/var/log/fsck/checkfs:                                         ASCII text
/var/log/kern.log:                                             ASCII text
/var/log/lastlog:                                              data
/var/log/lxd:                                                  directory
/var/log/syslog:                                               ASCII text
/var/log/unattended-upgrades:                                  directory
/var/log/unattended-upgrades/unattended-upgrades-shutdown.log: empty
/var/log/vboxadd-install-x11.log:                              ASCII text
/var/log/wtmp:                                                 data