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 protocol 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. 

AUTHOR

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

FUTURE DIRECTION

The default behavior in this release is still the classic HP-UX BSD Sockets, however it will be changed to X/Open Sockets in some future release.  At that time, any HP-UX BSD Sockets behavior which is incompatible with X/Open Sockets may be obsoleted.  HP customers are advised to migrate their applications to conform to X/Open specification( see xopen_networking(7) ). 

SEE ALSO

read(2), socket(2), write(2), xopen_networking(7). 

STANDARDS CONFORMANCE

socketpair(): XPG4

Hewlett-Packard Company  —  HP-UX Release 10.20:  July 1996