not PIN code, pass phrase

  In the HTTPS world, you use certificates to validate that you are the one

  you you claim to be, as an addition to normal passwords. Curl supports

  client-side certificates. All certificates are locked with a PIN-code, why

  you need to enter the unlock-code before the certificate can be used by

  curl. The PIN-code can be specified on the command line or if not, entered

  interactively when curl queries for it. Use a certificate with curl on a

  HTTPS server like:

  client-side certificates. All certificates are locked with a pass phrase,

  which you need to enter before the certificate can be used by curl. The pass

  phrase can be specified on the command line or if not, entered interactively

  when curl queries for it. Use a certificate with curl on a HTTPS server

  like:

        curl -E mycert.pem https://that.secure.server.com