CURLOPT_PINNEDPUBLICKEY.3: replace test.com with example.com

# - If you don't have sed, then just copy the certificate into a file:

#   Lines from -----BEGIN CERTIFICATE----- to -----END CERTIFICATE-----.

#

openssl s_client -servername www.test.com -connect www.test.com:443 < /dev/null | sed -n "/-----BEGIN/,/-----END/p" > www.test.com.pem

openssl s_client -servername www.example.com -connect www.example.com:443 < /dev/null | sed -n "/-----BEGIN/,/-----END/p" > www.example.com.pem

# extract public key in pem format from certificate

openssl x509 -in www.test.com.pem -pubkey -noout > www.test.com.pubkey.pem

openssl x509 -in www.example.com.pem -pubkey -noout > www.example.com.pubkey.pem

# convert public key from pem to der

openssl asn1parse -noout -inform pem -in www.test.com.pubkey.pem -out www.test.com.pubkey.der

openssl asn1parse -noout -inform pem -in www.example.com.pubkey.pem -out www.example.com.pubkey.der

# sha256 hash and base64 encode der to string for use

openssl dgst -sha256 -binary www.test.com.pubkey.der | openssl base64

openssl dgst -sha256 -binary www.example.com.pubkey.der | openssl base64

.fi

The public key in PEM format contains a header, base64 data and a

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