YESTERDAY(1) YESTERDAY(1)
NAME
yesterday - print file names from the dump
SYNOPSIS
yesterday [ -abcCdD ] [ -n daysago ] [ -date ] files ...
DESCRIPTION
Yesterday prints the names of the files from the most recent
dump. Since dumps are done early in the morning,
yesterday's files are really in today's dump. For example,
if today is March 17, 1992,
yesterday /adm/users
prints
/n/dump/1992/0317/adm/users
In fact, the implementation is to select the most recent
dump in the current year, so the dump selected may not be
from today.
By default, yesterday prints the names of the dump files
corresponding to the named files. The first set of options
changes this behavior.
-a Run acme(1)'s adiff to compare the dump files with the
named files.
-b Bind the dump files over the named files.
-c Copy the dump files over the named files.
-C Copy the dump files over the named files only when they
differ.
-d Run diff to compare the dump files with the named
files.
-D Run diff -n to compare the dump files with the named
files.
The date option selects other day's dumps, with a format of
1, 2, 4, 6, or 8 digits of the form d, dd, mmdd, yymmdd, or
yyyymmdd.
The -n option selects the dump daysago prior to the current
day.
Yesterday does not guarantee that the string it prints
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YESTERDAY(1) YESTERDAY(1)
represents an existing file.
EXAMPLES
Back up to yesterday's MIPS binary of vc:
yesterday -c /mips/bin/vc
Temporarily back up to March 1's MIPS C library to see if a
program runs correctly when loaded with it:
yesterday -b -0301 /mips/lib/libc.a
rm v.out
mk
v.out
Find what has changed in the C library since March 1:
yesterday -d -0301 /sys/src/libc/port/*.c
FILES
/n/dump
SOURCE
/rc/bin/yesterday
SEE ALSO
history(1), bind(1), diff(1), fs(4).
BUGS
It's hard to use this command without singing.
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