Date: Sat, 3 May 2003 02:03:30 +0200 From: Erik Trulsson <ertr1013@student.uu.se> To: Jerry McAllister <jerrymc@clunix.cl.msu.edu> Cc: freebsd-questions@freebsd.org Subject: Re: Zeros and ones Message-ID: <20030503000330.GA98398@falcon.midgard.homeip.net> In-Reply-To: <200305022353.h42NreOY018887@clunix.cl.msu.edu> References: <200305022353.h42NreOY018887@clunix.cl.msu.edu>
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On Fri, May 02, 2003 at 07:53:40PM -0400, Jerry McAllister wrote: > Hi, > > This should be easy, but short of writing something specific to do it, > I am not getting my head around how. > > It is easy and convenient to use /dev/zero to write out a number of > zero bytes to somewhere - as in: > > dd if=/dev/zero of=zerofile bs=512 count=1770000 > or > dd if=/dev/zero of=/dev/da1 bs=512 count=1770000 > > But, I would like to write all ones - as in 0xff or maybe some > other pattern - as if there was a /dev/one also. > > Is there a nice way to do this using UNIXistic stringing existing > stuff together? Or do I have to write a little piece of code? Of course there is a nice way. :-) Try something like tr '\000' '\377' < /dev/zero | dd of=onesfile bs=512 count=1770000 to get a file with all bits equal to one. -- <Insert your favourite quote here.> Erik Trulsson ertr1013@student.uu.se
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