Subject: Re: Shell hack -- getting files with dates
To: Jan Danielsson <jan.m.danielsson@gmail.com>
From: Steven M. Bellovin <smb@cs.columbia.edu>
List: netbsd-users
Date: 02/04/2007 12:42:47
On Sun, 04 Feb 2007 18:29:13 +0100
Jan Danielsson <jan.m.danielsson@gmail.com> wrote:

> Steven M. Bellovin wrote:
> [---]
> > The return code from egrep is specified by Posix, as I recall.
> 
>    Excellent.
> 
> >However
> > -- why not do
> > 	for f in
> > ~/backup/[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9].gpg
> 
>    The problem is that I need to process all the files, even those
> without a date -- it's just that I need to determine if they do
> contain a date, because they are handled a little differently.
> 
>   I have a backup in, say, /backup -- this is unencrypted -- but on an
> encrypted partition. Some files here contain dates (these are created
> twice a week), and others do not (these are created daily). For
> instance
> 
>    /backup
>       documents.2007-01-01.tar.bz2
>       documents.2007-01-04.tar.bz2
>       documents.2007-01-07.tar.bz2
>       documents.2007-01-10.tar.bz2
>       documents.tar.bz2              <- updated (overwritten) daily
> 

The shell is powerful, Luke:

for i in ~/backup/*
do
	case `basename $i` in
	[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9].gpg) one variant
		;;
	*)
		the other
		;;
	esac
done



		--Steve Bellovin, http://www.cs.columbia.edu/~smb