HP-UX Reference (11i v1 05/09) - 2 System Calls (vol 5)

socketpair(2) socketpair(2)

NAME

socketpair() - create a pair of connected sockets

SYNOPSIS

#include <sys/socket.h>

int socketpair(int af, int type, int protocol, int sv[2]);

DESCRIPTION

The socketpair() system call creates an unnamed pair of connected sockets and returns two ﬁle

descriptors in sv[0] and sv[1]. The two sockets are indistinguishable. af speciﬁes the address family. See

socket(2). type speciﬁes the semantics of communication for the socket. protocol speciﬁes a particular pro-

tocol to be used. protocol can be speciﬁed as zero, which causes the system to choose a protocol type to use.

RETURN VALUE

socketpair() returns the following values:

0 Successful completion.

-1 Failure. errno is set to indicate the error.

ERRORS

If socketpair() fails, errno is set to one of the following values.

[EAFNOSUPPORT] The speciﬁed address family is not supported in this version of the system.

[EFAULT] The sv parameter is not valid.

[EMFILE] The per-process ﬁle descriptor table is full.

[ENFILE] The system ﬁle table is temporarily full.

[ENOBUFS] No buffer space is available for the operation to complete.

[EOPNOTSUPP] The speciﬁed protocol does not support creation of socket pairs.

[EPROTONOSUPPORT]

The speciﬁed protocol is not supported in this version of the system.

DEPENDENCIES

socketpair() is supported only for AF_UNIX.

FUTURE DIRECTION

Currently, the default behavior is the HP-UX BSD Sockets; however, it might be changed to X/Open

Sockets in a future release. At that time, any HP-UX BSD Sockets behavior that is incompatible with

X/Open Sockets might be obsoleted. Applications that conform to the X/Open speciﬁcation now will avoid

migration problems (see xopen_networking(7)).

AUTHOR

socketpair() was developed by HP and the University of California, Berkeley.