Are UNIX sockets bidirectional?

Sockets are bidirectional, providing a two-way flow of data between processes that may or may not have the same parent. Pipes provide a similar functionality. However, they are unidirectional, and they can be used only between processes that have the same parent.

What is a Unix socket connection?

A Unix domain socket or IPC socket (inter-process communication socket) is a data communications endpoint for exchanging data between processes executing on the same host operating system. Valid socket types in the UNIX domain are: SOCK_STREAM (compare to TCP) – for a stream-oriented socket.

How do UNIX domain sockets work?

Unix sockets are bidirectional. This means that every side can perform both read and write operations. While, FIFOs are unidirectional: it has a writer peer and a reader peer. Unix sockets create less overhead and communication is faster, than by localhost IP sockets.

Are UNIX sockets TCP?

Sockets usually still use TCP or UDP, as they aren’t anything special other than a fancy pipe within the kernel. TCP and UDP are transport protocols that define how data gets from place to place but don’t really care about what the data is.

Do Unix sockets have ports?

When a client process wants to a connect a server, the client must have a way of identifying the server that it wants to connect. The port assignments to network services can be found in the file /etc/services. …

Where do I put a UNIX socket?

Unix sockets only live while the program is running, so /tmp/ is usually an alright place for them to live, some programs chose to put them into /var/run/ (since while they are in essence “temporary”, they have persistent names).

Are UNIX sockets secure?

In short, Unix domain sockets are secure in general. You can use POSIX permissions to lock down access to the file descriptor (FD) associated with the socket, and the server side can request information such as credentials and PID of clients before they can fully connect.

Does unix socket need port?

When a client process wants to a connect a server, the client must have a way of identifying the server that it wants to connect. If you are writing your own server then care must be taken to assign a port to your server. …

Are UNIX sockets faster than TCP?

Depending on the platform, unix domain sockets can achieve around 50\% more throughput than the TCP/IP loopback (on Linux for instance). The default behavior of redis-benchmark is to use the TCP/IP loopback.

Where do I put a unix socket?

Are UNIX domain sockets reliable?

Valid socket types in the UNIX domain are: SOCK_STREAM, for a stream-oriented socket; SOCK_DGRAM, for a datagram-oriented socket that preserves message boundaries (as on most UNIX implementations, UNIX domain datagram sockets are always reliable and don’t reorder datagrams); and (since Linux 2.6.

What is the use of sockets in Unix?

Sockets allow communication between two different processes on the same or different machines. To be more precise, it’s a way to talk to other computers using standard Unix file descriptors. In Unix, every I/O action is done by writing or reading a file descriptor.

Can I send a socket over TCP to another machine?

@AdrianRatnapala: no, you can’t send a socket (or file handle) over TCP to another machine, they must stay within the same kernel. So the channel over which you communicate must be AF_UNIX, but the file handle you transfer can of course be a TCP socket.

What is the AF_UNIX socket?

The AF_UNIX (also known as AF_LOCAL ) socket family is used to communicate between processes on the same machine efficiently. Traditionally, UNIX domain sockets can be either unnamed, or bound to a filesystem pathname (marked as being of type socket). Linux also supports an abstract namespace which is independent of the filesystem.

Is the send(2) MSG_more flag supported by Unix domain sockets?

The send (2) MSG_MORE flag is not supported by UNIX domain sockets. Before Linux 3.4, the use of MSG_TRUNC in the flags argument of recv (2) was not supported by UNIX domain sockets. The SO_SNDBUF socket option does have an effect for UNIX domain sockets, but the SO_RCVBUF option does not.