.TH HISTORY 1
.SH NAME
history \- print file names from the dump
.SH SYNOPSIS
.B history
[
.B -vDu
] [
.B -d
.I dumpfilesystem
] [
.B -s
.I yymmdd
]
.I files ...
.SH DESCRIPTION
.I History
prints the names, dates, and sizes of all versions of the named
.IR files ,
looking backwards in time,
stored in the dump file system.
For example,
.IP
.EX
history /adm/users
.EE
.PP
produces
.IP
.EX
Jan  5 18:24:05 EST 1998 /adm/users 6945
Dec 19 10:16:06 EST 1997 /n/dump/1998/0105/adm/users 6945
Dec 16 11:37:12 EST 1997 /n/dump/1997/1219/adm/users 6926
Dec  3 15:46:00 EST 1997 /n/dump/1997/1216/adm/users 6910
	...
.EE
.PP
The
.B -v
option enables verbose debugging printout.
.PP
The 
.B -D
option causes
.IR diff (1)
.B -n
to be run for each adjacent pair of files, while
.B -b
runs
.IR diff
.BR -nb .
.PP
The
.B -u
option causes times to be printed in GMT (UT) rather than local time.
.PP
The
.B -d
option selects some other dump filesystem such as
.IR /n/bootesdump .
.PP
Finally, the
.B -s
option
sets the starting (most recent) date for the output.
.SH EXAMPLES
.PP
Check how often a user has been logged in.
.IP
.EX
history /usr/ches/tmp
.EE
.SH FILES
.B /n/dump
.SH SOURCE
.B /sys/src/cmd/history.c
.SH SEE ALSO
.IR fs (4)
.br
.IR yesterday (1)