A Unix domain socket or IPC socket (inter-procedure call socket) is a virtual socket, similar to an internet socket that is used in POSIX operating systems for inter-process communication. The correct standard POSIX term is POSIX Local IPC Sockets.

These connections appear as a byte stream network connection but go from the local computer to itself.

In addition to sending data, processes can send file descriptors across a Unix domain socket connection using the sendmsg() and recvmsg() system calls.

External links

• socketpair(2) man page: create a pair of connected sockets
• sendmsg(2) man page
• recvmsg(2) man page
• cmsg(3) man page: socket ancillary data, including sending/receiving file descriptors

Unix | Inter-process communication