Hi, I have the same issue. The problem seems to be in auth-juniper.c:369 if (socketpair(AF_UNIX, SOCK_SEQPACKET, 0, sockfd)) { The code does not print any error there. added perror prints ?protocol not supported?. OS X does not seem to support the type SEQPACKET. From man socket: The socket has the indicated type, which specifies the semantics of communication. Currently defined types are: SOCK_STREAM SOCK_DGRAM SOCK_RAW On that note. Is there any chance you could talk to the tncc-socket directly without the std-in-redirect and thus needing the preloader? -- Alex