Finding Return Code From GPG

[Nomen Nescio]

I'm running gpg in python to verify a signature. I can see that it is
working, because gpg is displaying the results.

But I need a way to let the python script know this. According to the gpg
manual there is a return code from gpg of 0 if the verify is good and 1 if
it is bad.

Can anyone tell me how I can get the python script to 'see' this return
code?

[Dennis Benzinger]

Re: Finding Return Code From GPG

Nomen Nescio wrote:

I'm running gpg in python to verify a signature. I can see that it is
working, because gpg is displaying the results.
>
But I need a way to let the python script know this. According to the gpg
manual there is a return code from gpg of 0 if the verify is good and 1 if
it is bad.
>
Can anyone tell me how I can get the python script to 'see' this return
code?
>

How do you run GPG? I suggest using the subprocess module
<http://docs.python.org/lib/module-subprocess.html >. If you just need
something simple then you can use its call function
<http://docs.python.org/lib/node236.html>.


Bye,
Dennis

[Martin Renold]

Re: Finding Return Code From GPG

* Dennis Benzinger <Dennis.Benzing er@gmx.net>:

Nomen Nescio wrote:

I'm running gpg in python to verify a signature.
But I need a way to let the python script know this.

I have written a script to verify signatures using gpg some time
ago, maybe this helps you:

http://old.homeip.net/martin/sigcheck/

bye
Martin

[Nomen Nescio]

Re: Finding Return Code From GPG

On Tue, 04 Jul 2006 19:00:23 +0200, Dennis Benzinger wrote:

Nomen Nescio wrote:

>I'm running gpg in python to verify a signature. I can see that it is
>working, because gpg is displaying the results.
>>
>But I need a way to let the python script know this. According to the
>gpg manual there is a return code from gpg of 0 if the verify is good
>and 1 if it is bad.
>>
>Can anyone tell me how I can get the python script to 'see' this return
>code?
>>
>>

How do you run GPG? I suggest using the subprocess module
<http://docs.python.org/lib/module-subprocess.html >. If you just need
something simple then you can use its call function
<http://docs.python.org/lib/node236.html>.

Thanks, I used the popen function which did some of what I want. Here is
the code I used:


from subprocess import *

output = Popen(["gpg", "--output", "--verify", "sigtest"], stdout=PIPE).co mmunicate()[0]



That worked, sort of - it did the verification at least and I can see the return code.

What is still not working is the display from gpg. It shows up on the monitor screen like this:

gpg: Signature made Tue 04 Jul 2006 08:04:10 AM CET using DSA key ID
06B09BA4
gpg: Good signature from "Boz Scraggs <scraggs@test.i nvalid>"


I need to get that into a file so I can parse it. Any further suggestions?

[Piet van Oostrum]

Re: Finding Return Code From GPG

>>>>Nomen Nescio <nobody@dizum.c om(NN) wrote:

>NNThanks, I used the popen function which did some of what I want. Here is
>NNthe code I used:

>NNfrom subprocess import *

>NNoutput = Popen(["gpg", "--output", "--verify", "sigtest"], stdout=PIPE).co mmunicate()[0]

You need a filename argument for --output.

>NNThat worked, sort of - it did the verification at least and I can see
>NNthe return code.

>NNWhat is still not working is the display from gpg. It shows up on the
>NNmonitor screen like this:

>NNgpg: Signature made Tue 04 Jul 2006 08:04:10 AM CET using DSA key ID
>NN06B09BA4
>NNgpg: Good signature from "Boz Scraggs <scraggs@test.i nvalid>"

>NNI need to get that into a file so I can parse it. Any further suggestions?

That output is passed to stderr. So you can get it in a string:

output = Popen(["gpg", "--output", "outfile", "--verify", "sigtest"], stderr=PIPE).co mmunicate()[1]
--
Piet van Oostrum <piet@cs.uu.n l>
URL: http://www.cs.uu.nl/~piet [PGP 8DAE142BE17999C 4]
Private email: piet@vanoostrum .org

[Nomen Nescio]

Re: Finding Return Code From GPG

On Sat, 08 Jul 2006 00:26:06 +0200, Piet van Oostrum wrote:

>

>>NNWhat is still not working is the display from gpg. It shows up on the
>>NNmonitor screen like this:

>

>>NNgpg: Signature made Tue 04 Jul 2006 08:04:10 AM CET using DSA key ID
>>NN06B09BA4
>>NNgpg: Good signature from "Boz Scraggs <scraggs@test.i nvalid>"

>

>>NNI need to get that into a file so I can parse it. Any further suggestions?

>
That output is passed to stderr. So you can get it in a string:
>
output = Popen(["gpg", "--output", "outfile", "--verify", "sigtest"], stderr=PIPE).co mmunicate()[1]

That worked, thanks very much; and my thanks to all who replied.