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create gpg key

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Download and install gpg (in ubuntu gpg is alredy installed)

gpg --full-generate-key

select RSA and RSA (default)

select 4096 keysize

specify how long the key should be valid (0 default)

enter your name (id github exemple)

enter your email address (like github email adress /!\ important)

veryfy with O

enter paraphrase

copy the id of rsa key

pub rsa4096 2023-08-04 [SC] **************************************** <---- this is rsa id uid *********name and email******* sub rsa4096 2023-08-04 [E]

for get your gpg key:

gpg --list-secret-keys --keyid-format=long

past this id in this command:

gpg --armor --export ****************************************(rsa id)

Copy your GPG key, beginning with -----BEGIN PGP PUBLIC KEY BLOCK----- and ending with -----END PGP PUBLIC KEY BLOCK-----.

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add to your github account

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In the upper-right corner of any page, click your profile photo, then click Settings.

In the "Access" section of the sidebar, click SSH and GPG keys.

Next to the "GPG keys" header, click New GPG key.

In the "Title" field, type a name for your GPG key.

In the "Key" field, paste the GPG key you copied at precedent step.

Click Add GPG key.

To confirm the action, authenticate to your GitHub account.

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Telling Git about your signing key

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git config --global --unset gpg.format sec rsa4096/*****->copy this id<-****** 2023-08-04 [SC] **************************************** uid [ultimate] ******email***** ssb rsa4096/*************** 2023-08-04 [E] git config --global user.signingkey [******your id*******]

Optionally, to configure Git to sign all commits by default, enter the following command:

git config --global commit.gpgsign true

initial tuto : here

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