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Date: Sat, 6 Aug 2005 09:50:40 +0200
From: Michal Politowski <mpol@charybda.icm.edu.pl>
To: zsh-users@sunsite.dk
Subject: Re: RFT: Request for a trick :O)
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References: <20050806.065638.92586082.Meino.Cramer@gmx.de>
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On Sat,  6 Aug 2005 06:56:38 +0200, Meino Christian Cramer wrote:
[...]
> 	 cmp < `7z x -so foo.7z` < `7z x -so bar.7z`
>=20
>  may work I thought...but it doesnt (the assumption was totally
>  wrong)...  ( "7z x -so <file>.7z" means "unpack <file>.7z to stdout)
>=20
>  But...may be someone else knows a tricky way to prevent temporary
>  files to compare the (single file) contents of two archives in one
>  go???

Almost there. Read about process substitution in the documentation.
It looks like <(command), >(command) and =3D(command)
so in your case
cmp <(7z x -so foo.7z) <(7z x -so bar.7z)
should work.

--=20
Micha=B3 Politowski
Talking has been known to lead to communication if practiced carelessly.