history – print file names from the dump

history [ –Dabcemnw ] [ –fu ] [ –d dumpfilesystem ] [ –s yyyymmdd ] files ...

History prints the names, dates, and sizes, and modifier of all versions of the named files, looking backwards in time, stored in the dump file system. If the file exists in the main tree, the first line of output will be its current state. For example,
history /adm/users

May 14 15:29:18 EDT 2001 /adm/users 10083 [adm]
May 14 15:29:18 EDT 2001 /n/dump/2001/0515/adm/users 10083 [adm]
May 11 17:26:24 EDT 2001 /n/dump/2001/0514/adm/users 10481 [adm]
May 10 16:40:51 EDT 2001 /n/dump/2001/0511/adm/users 10476 [adm]

The –D option causes diff(1) to be run for each adjacent pair of dump files. The options –abcemnw are passed through to diff; the little–used diff option –f is replaced by the functionality described below, and the –r option is disallowed.

The –u option causes times to be printed in GMT (UT) rather than local time.

The –d option selects some other dump file system such as /n/bootesdump.

The –f option is accepted but ignored by compatibility with other history implementations.

Finally, the –s option sets the starting (most recent) date for the output.

Check how often a user has been logged in.
history /usr/ches/tmp



fs(4), yesterday(1)