SOCKETPAIR Section: Linux Programmer's Manual (2) Updated: 24 July 2025 Index   NAME socketpair - create a pair of connected sockets   SYNOPSIS #include <sys/types.h> #include <sys/socket.h> int socketpair(int d, int type, int protocol, int sv[2]);   DESCRIPTION The call creates an unnamed pair of connected sockets in the specified domain d, of the specified type, and using the optionally specified protocol. The descriptors used in referencing the new sockets are returned in sv[0] and sv[1]. The two sockets are indistinguishable.   RETURN VALUE On success, zero is returned. On error, -1 is returned, and errno is set appropriately.   ERRORS EMFILE Too many descriptors are in use by this process. EAFNOSUPPORT The specified address family is not supported on this machine. EPROTONOSUPPORT The specified protocol is not supported on this machine. EOPNOSUPPORT The specified protocol does not support creation of socket pairs. EFAULT The address sv does not specify a valid part of the process address space.   CONFORMING TO 4.4BSD (the socketpair function call appeared in 4.2BSD). Generally portable to/from non-BSD systems supporting clones of the BSD socket layer (including System V variants).   SEE ALSO   Index NAME SYNOPSIS DESCRIPTION RETURN VALUE ERRORS CONFORMING TO SEE ALSO This document was created by using the manual pages. Time: 11:56:07 GMT, March 24, 2025