Cargo Features

[dependencies]
gex-sys = { version = "0.1.0", default-features = false, features = ["udp", "mpi", "ibv"] }
default = udp

The udp feature is set by default whenever gex-sys is added without default-features = false somewhere in the dependency tree.

udp default
mpi
ibv

gex-sys has 4 features without comments.