=> Bootstrap dependency digest>=20010302: found digest-20160304
=> Fetching zeromq-4.1.4.tar.gz
=> Total size: 1400012 bytes
ftp: Error retrieving file `404 Not Found'
fetch: Unable to fetch expected file zeromq-4.1.4.tar.gz
=> Checksum SHA1 OK for zeromq-4.1.4.tar.gz
=> Checksum RMD160 OK for zeromq-4.1.4.tar.gz
=> Checksum SHA512 OK for zeromq-4.1.4.tar.gz