From: Eric Hodel <drbrain@...7.net>
Date: 2003-10-02T22:19:16-07:00
Subject: Re: backquotes, system, shell and ruby


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John Carter (john.carter@tait.co.nz) wrote:

> Consider backquotes.
>=20
> a =3D `wc *.c`
>=20
> What did that do? Same as open("|wc *.c").
>=20
> It ran bash!
>=20
> Yuck!
>=20
> system( "tar -xvzf foo.tgz foo")
>=20
> What did that do? It ran shell!
>=20
> Why? Why does a scripting language like Ruby keep invoking an old and bad
> scripting language call shell?

Because that's what system(3) does, check the man page.

Perl does it, and if I had a Python installed, I bet python would do it
too.  If you want it to not run in a shell, use fork and exec.

--=20
Eric Hodel - drbrain@segment7.net - http://segment7.net
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