Sample decryption command lines

Gpg4win help-en
1

Where can I find example / sample decryption command lines for gpg4win, I am very new to this and just need to write a process that will decrypt one file per day with no user intervention.

2

Hi Isaac,

the crypto engine of Gpg4win is called GnuPG.
And GnuPG is a crossplatform application, so except for minor differences the documentation you can find work the same on GNU/Linux system, Mac OS and Windows systems.

The examples from the full technical manual can be found here:
https://gnupg.org/documentation/manuals/gnupg/GPG-Examples.html#GPG-Examples

(The documentation also is installed together with Gpg4win.)

Best,
Bernhard

3

Thanks, but I am so new at this that when I see and read the help files they are very confusing to me, so many different programs, systems, referenced which I am not familiar with.
So when I am under the page https://gnupg.org/documentation/manuals/gnupg/Option-Index.html#Option-Index and under “decrypt” section (under the D section), do you know which one of the 4 decrypt categories would pertain best to me? if all I want to do is command line decrypt a file?

4

Hi Isaac,

gpg is the command for OpenPGP messages. Use
gpg --decrypt FILE
if you have OpenPGP encrypted files. (Note that you will also have to have access
to the private key material, one way to do it is to use a key without passphrase, that you secure sufficiently, another is to enter the passphrase and have gpg-agent cache it indefinately.)

gpgsm is the command for CMS objects (as used with S/MIME mails). You probably don’t want this for files.

gpgtar is if you use archives for a bundle of files and directories, (which you wrote you did not want).

--decrypt-files is like `–multiple-file’ when you want to decrypt several files after each other in one command ( which you wrote you did not want).

Best Regards,
Bernhard

5

When I used the decrypt - gpg option, I found --decrypt. “decrypts the file on the command line or on stdin”. but it didnt’t give an example of the syntax, frustrating my best efforts.

Am I to assume “decrypts the file on the command line” means (well all of this is on a command line isn’t it??) that the syntax might be

–decrypt “filepath”

…and then what about the commands for path to private key asc file? what about path to output file?

I thought I would search stdin and stdout to see what that was all about, but almost didn’t find them at all in index, except for some sentences referring to them but not explaining them.

6

Hi,
too cite from https://gnupg.org/documentation/manuals/gnupg/Operational-GPG-Commands.html#Operational-GPG-Commands

“”"
–decrypt
-d

Decrypt the file given on the command line (or STDIN if no file is specified) and write it to STDOUT (or the file specified with --output). If the decrypted file is signed, the signature is also verified. This command differs from the default operation, as it never writes to the filename which is included in the file and it rejects files that don’t begin with an encrypted message.

“”"

Here is an explanation what STDIN and STDOUT are
https://en.wikipedia.org/wiki/Standard_streams#Standard_output_(stdout)

So if you give something like
gpg --decrypt --output FILEPATH FILEPATH
it should work.
I suggest you just create a few test keys and files and run it through a few interations to see how it works.

Best Regards,
Bernhard

7

thank you! I missed the output part , I see it now. I have requested to corporate I.T. to install gpg4win on my pc so I can test, looking forward to being able to.