Very Computer

I've been using
DATE = `date +%y%m%d`
to print the date in YYMMDD format, but what I'd like to do is
use this (or another simple way) to get yesterdays date in the
same format.

If there is a way to do it in perl, that is acceptable too.
I could write a routine to figure it out, but if there is a short hand
way of determining it, that would be best.

Thanks,

Jay

|> I've been using
|> DATE = `date +%y%m%d`
|> to print the date in YYMMDD format, but what I'd like to do is
|> use this (or another simple way) to get yesterdays date in the
|> same format.
|>
|> If there is a way to do it in perl, that is acceptable too.
|> I could write a routine to figure it out, but if there is a short hand
|> way of determining it, that would be best.
|>
|> Thanks,
|>
|> Jay
|>

Add 24 to the offset in your TZ enviroment variable, e.g.

TZ=EST29EDT date +%y%m%d

John> I've been using
John> DATE = `date +%y%m%d`
John> to print the date in YYMMDD format, but what I'd like to do is
John> use this (or another simple way) to get yesterdays date in the
John> same format.

John> If there is a way to do it in perl, that is acceptable too.
John> I could write a routine to figure it out, but if there is a short hand
John> way of determining it, that would be best.

        perl -e 'printf "%02d%02d%02d", (localtime time-86400)[5,4,3]'

Just another Perl hacker,
--
Name: Randal L. Schwartz / Stonehenge Consulting Services (503)777-0095
Keywords: Perl training, UNIX[tm] consulting, video production, skiing, flying

Web: <A HREF="http://www.teleport.com/~merlyn/">My Home Page!</A>
Quote: "I'm telling you, if I could have five lines in my .sig, I would!" -- me

The GNU date() utility has a '--date' option that accepts a string as a
value.  The command will subsequently return the date associated with
the string value.  Valid string values are "yesterday" and "2 days ago",
among others.

Ain't GNU wonderful!

        date -d yesterday +%y%m%d

--
Copyright 1996 by Doc O'Leary.
Author of the wildly unsuccessful "DOS and Windows for People Who
Still Have a Clue"

--
--------------------------------------------------------------------------------

Quote:(John Wright) writes:
> I've been using
> DATE = `date +%y%m%d`
> to print the date in YYMMDD format, but what I'd like to do is
> use this (or another simple way) to get yesterdays date in the
> same format.

Hope this help.

Ciao, Alex.

Quote:>}   date -d yesterday +%y%m%d
>}
>That might be "right" on you OS but is dont work on SCO 3.2.2

Time to install gnu date.

--
      Artificial Intelligence stands no chance against Natural Stupidity.
                GAT d- -p+(--) c++++ l++ u++ t- m--- W--- !v
                     b+++ e* s-/+ n-(?) h++ f+g+ w+++ y*

#!/bin/sh
#
#  Program: yesterday
#   Author: Randall Schwartz
#  Purpose: Prints yesterday's date
#
perl -e 'printf "%s\n", scalar localtime (time - 86400)'

Hope that helps.

Best regards,

Lawson Hanson

Lawson> If you have Perl-5 installed, then you can use:

Lawson> #!/bin/sh
Lawson> #
Lawson> #  Program: yesterday
Lawson> #   Author: Randall Schwartz
Lawson> #  Purpose: Prints yesterday's date
Lawson> #
Lawson> perl -e 'printf "%s\n", scalar localtime (time - 86400)'

Ouch.  That hurts, unless you're talking about some other Randall [sic]
Schwartz.

My version was merely:

        perl -e 'print scalar localtime (time - 86400)'

No need to make the trip into printf land.  (My friends would be so
embarassed for me if they thought I wrote code like that. :-)

Just another Perl hacker,
--
Name: Randal L. Schwartz / Stonehenge Consulting Services (503)777-0095
Keywords: Perl training, UNIX[tm] consulting, video production, skiing, flying

Web: <A HREF="http://www.teleport.com/~merlyn/">My Home Page!</A>
Quote: "I'm telling you, if I could have five lines in my .sig, I would!" -- me

Use GNU date:

/opt/local/gnu/bin/date --date '2 days ago'

And it almost looks like it was written by a human being ;)
Assuming of course (like perl) you have it on your system!

In UNIX, there is always one more way to defer a feline ;)
(not a useless use of cat)

sorry ;)

rachel

--
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                Witty comment revoked due to funding cuts

--
Andy Walker, Maths Dept., Nott'm Univ., UK.

Quote:> Use GNU date:

> /opt/local/gnu/bin/date --date '2 days ago'

- last day of last month
- last day of February last year

Thanks,
Geoff..

Here's a relatively simple shell script to get yesterday's
date.  This solution hit me over the head about a month ago.

:
# calculate yesterdays date
echo "Now is `date`"
p=`echo $TZ | cut -c1-3`
d=`echo $p | tr S D`
o=`echo $TZ | tr -d [A-Z]`
y=`expr $o + 24`
TZ=`echo $p$y$d`
echo "Yesterday was `date`"

Quote:># calculate yesterdays date
>echo "Now is `date`"
>p=`echo $TZ | cut -c1-3`
>d=`echo $p | tr S D`
>o=`echo $TZ | tr -d [A-Z]`
>y=`expr $o + 24`
>TZ=`echo $p$y$d`
>echo "Yesterday was `date`"

$ uname -a; echo $TZ
SunOS techsrv1 5.5 Generic sun4c sparc SUNW,Sun_4_50
US/Eastern

$ uname -a; echo $TZ
OSF1 rtdu56.bpw.ous.bp.com V3.2 148 alpha

$ uname -a; echo $TZ
Linux techsrv10 2.0.0 #1 Tue Jun 25 12:14:29 GMT 1996 i486

$ uname -a; echo $TZ
ULTRIX www.ous.bp.com 4.4 0 RISC

and so on....  But on systems where this does work, it's rather clever.
I like it. :-)

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