Linux 解决 public key is not available 问题
现象
W: GPG error: http://ppa.launchpad.net jaunty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 12DE1BCB04E5E17B5
$ gpg --keyserver keyserver.ubuntu.com --recv 4E5E17B5 # 返回信息gpg: requesting key 4E5E17B5 from hkp server keyserver.ubuntu.comgpg: key 4E5E17B5: public key "Launchpad PPA for chromium-daily" importedgpg: no ultimately trusted keys foundgpg: Total number processed: 1gpg: imported: 1 (RSA: 1)
$ gpg --export --armor 4E5E17B5 | sudo apt-key add - # 返回信息OK
