Thx Tim for help.
Now I'm using another user than root... But I'm still in a black hole (+headache), sadly without finding any document about how using this "go" software + obfs4 :'(
Sooory, I'm not really nice with source compiling... :s
_go help gopath :_ [...] Each directory listed in GOPATH must have a prescribed structure:
The src/ directory holds source code. The path below 'src' determines the import path or executable name.
The pkg/ directory holds installed package objects. As in the Go tree, each target operating system and architecture pair has its own subdirectory of pkg (pkg/GOOS_GOARCH). [...]
But I don't see any /src or /pkg in the downloaded git folder ?
_Here the content downloaded :_ $ dir -R /home/petrusko/obfs4/
obfs4/: ChangeLog common doc LICENSE obfs4proxy README.md transports
obfs4/common: csrand drbg log ntor probdist replayfilter socks5 uniformdh
obfs4/common/csrand: csrand.go
obfs4/common/drbg: hash_drbg.go
obfs4/common/log: log.go
obfs4/common/ntor: ntor.go ntor_test.go
obfs4/common/probdist: weighted_dist.go weighted_dist_test.go
obfs4/common/replayfilter: replay_filter.go replay_filter_test.go
obfs4/common/socks5: args.go args_test.go rfc1929.go socks5.go socks_test.go
obfs4/common/uniformdh: uniformdh.go uniformdh_test.go
obfs4/doc: obfs4proxy.1 obfs4-spec.txt
obfs4/obfs4proxy: obfs4proxy.go proxy_http.go proxy_socks4.go pt_extras.go termmon.go termmon_linux.go
obfs4/transports: base meeklite obfs2 obfs3 obfs4 scramblesuit transports.go
obfs4/transports/base: base.go
obfs4/transports/meeklite: base.go meek.go
obfs4/transports/obfs2: obfs2.go
obfs4/transports/obfs3: obfs3.go
obfs4/transports/obfs4: framing handshake_ntor.go handshake_ntor_test.go obfs4.go packet.go statefile.go
obfs4/transports/obfs4/framing: framing.go framing_test.go
obfs4/transports/scramblesuit: base.go conn.go handshake_ticket.go handshake_uniformdh.go hkdf_expand.go