Comtrol eCos - Manual (Page 578)

Chapter 38. TCP/IP Library Reference
RETURN VALUES
A 0 is returned if the call succeeds, -1 if it fails.
ERRORS
The call succeeds unless:
[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.
[EOPNOTSUPP] 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.
[ENFILE] The system file table is full.
SEE ALSO
pipe(2), read(2), write(2)
BUGS
This call is currently implemented only for the LOCAL domain. Many oper-
ating systems only accept a protocol of PF_UNSPEC, so that should be used
instead of PF_LOCAL for maximal portability.
STANDARDS
The socketpair() function conforms to X/Open Portability Guide Issue 4.2
(“XPG4.2”).
HISTORY
The socketpair() function call appeared in 4.2BSD.
BSD June 4, 1993 BSD
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