Return codes of unsuccessful gpg --verify

[Jody McIntyre]

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I am using gpg to verify a signed XML file from a Perl script.  I have been
relying on the return code to inform me if verification has been successful.
However, when the data is simply stored, not signed, verification returns 0
despite nothing being verified:

[jodym@jodym1 bla]$ gpg --store Packages.xml
[jodym@jodym1 bla]$ gpg --verify Packages.xml.gpg=20
[jodym@jodym1 bla]$ echo $?
0

Compare this to the behaviour for a BAD signature:

[jodym@jodym1 bla]$ gpg --sign Packages.xml

You need a passphrase to unlock the secret key for
user: "Jody McIntyre <jodym@oeone.com>"
1024-bit DSA key, ID E2B11082, created 2000-11-27

[jodym@jodym1 bla]$ vi Packages.xml.gpg   # Corrupt the file =20
[jodym@jodym1 bla]$ gpg --verify Packages.xml.gpg
gpg: Signature made Sat 18 Aug 2001 03:32:24 PM EDT using DSA key ID E2B110=
82
gpg: BAD signature from "Jody McIntyre <jodym@oeone.com>"
[jodym@jodym1 bla]$ echo $?
1

Is there any reliable way to determine if a package could be verified?  Do
I need to look for "Good signature" in gpg's output?

Thanks,
Jody
--=20
Jody McIntyre, jodym@oeone.com - OEone Corporation, Hull, Quebec, Canada

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