-S FILE (conditional operator)

true if the file exists and is a socket.

Links

• Unix domain socket on Wikipedia
• Bash manual
• POSIX specification of test

Examples

Different ways to test if a file is a socket:

1 2 3 4

test -S ~/file && echo "socket" [ -S ~/file ] && echo "socket" # Bash [[ -S ~/file ]] && echo "socket"