.\" Licensed under the OpenIB.org BSD license (FreeBSD Variant) - See COPYING.md
.TH "RDMA_GETADDRINFO" 3 "2010-07-19" "librdmacm" "Librdmacm Programmer's Manual" librdmacm
.SH NAME
rdma_getaddrinfo \- Provides transport independent address translation.
.SH SYNOPSIS
.B "#include <rdma/rdma_cma.h>"
.P
.B "int" rdma_getaddrinfo
.BI "(const char *" node ","
.BI "const char *" service ","
.BI "const struct rdma_addrinfo *" hints ","
.BI "struct rdma_addrinfo **" res ");"
.SH ARGUMENTS
.IP "node" 12
Optional, name, dotted-decimal IPv4, or IPv6 hex address to resolve.
.IP "service" 12
Service name or port number of address.
.IP "hints" 12
Reference to an rdma_addrinfo structure containing hints about the type
of service the caller supports.
.IP "res" 12
A pointer to a linked list of rdma_addrinfo structures containing response
information.
.SH "DESCRIPTION"
Resolves the destination node and service address and returns
information needed to establish communication.  Provides the
RDMA functional equivalent to getaddrinfo.
.SH "RETURN VALUE"
Returns 0 on success, or -1 on error (errno will be set to indicate the failure
reason), or one of the following nonzero error codes:
.IP "EAI_ADDRFAMILY" 12
The specified network host does not have any network addresses in the
requested address family.
.IP "EAI_AGAIN" 12
The name server returned a temporary failure indication. Try again later.
.IP "EAI_BADFLAGS" 12
hints.ai_flags contains invalid flags.
.IP "EAI_FAIL" 12
The name server returned a permanent failure indication.
.IP "EAI_FAMILY" 12
The requested address family is not supported.
.IP "EAI_MEMORY" 12
Out of memory.
.IP "EAI_NODATA" 12
The specified network host exists, but does not have any network addresses
defined.
.IP "EAI_NONAME" 12
The node or service is not known; or both node and service are NULL.
.IP "EAI_SERVICE" 12
The requested service is not available for the requested QP type. It may be
available through another QP type.
.IP "EAI_QPTYPE" 12
The requested socket type is not supported. This could occur, for example,
if hints.ai_qptype and hints.ai_port_space are inconsistent (e.g., IBV_QPT_UD
and RDMA_PS_TCP, respectively).
.IP "EAI_SYSTEM" 12
Other system error, check errno for details.
The gai_strerror() function translates these error codes to a human readable
string, suitable for error reporting.
.SH "NOTES"
Either node, service, or hints must be provided.  If hints are provided, the
operation will be controlled by hints.ai_flags.  If RAI_PASSIVE is
specified, the call will resolve address information for use on the
passive side of a connection.
If node is provided, rdma_getaddrinfo will attempt to resolve the RDMA address,
route, and connection data to the given node.  The hints parameter, if provided,
may be used to control the resulting output as indicated below.
If node is not given, rdma_getaddrinfo will attempt to resolve the RDMA addressing
information based on the hints.ai_src_addr, hints.ai_dst_addr, or hints.ai_route.
.SH "rdma_addrinfo"
.IP "ai_flags" 12
Hint flags that control the operation.  Supported flags are:
.IP "RAI_PASSIVE" 12
Indicates that the results will be used on the passive/listening
side of a connection.
.IP "RAI_NUMERICHOST" 12
If specified, then the node parameter, if provided, must be a numerical
network address.  This flag suppresses any lengthy address resolution.
.IP "RAI_NOROUTE" 12
If set, this flag suppresses any lengthy route resolution.
.IP "RAI_FAMILY" 12
If set, the ai_family setting should be used as an input hint for interpretting
the node parameter.
.IP "ai_family" 12
Address family for the source and destination address.  Supported families
are: AF_INET, AF_INET6, and AF_IB.
.IP "ai_qp_type" 12
Indicates the type of RDMA QP used for communication.  Supported types are:
IBV_QPT_UD (unreliable datagram) and IBV_QPT_RC (reliable connected).
.IP "ai_port_space" 12
RDMA port space in use.  Supported values are: RDMA_PS_UDP, RDMA_PS_TCP,
and RDMA_PS_IB.
.IP "ai_src_len" 12
The length of the source address referenced by ai_src_addr.  This will be 0
if an appropriate source address could not be discovered for a given
destination.
.IP "ai_dst_len" 12
The length of the destination address referenced by ai_dst_addr.  This
will be 0 if the RAI_PASSIVE flag was specified as part of the hints.
.IP "ai_src_addr" 12
If provided, the address for the local RDMA device.
.IP "ai_dst_addr" 12
If provided, the address for the destination RDMA device.
.IP "ai_src_canonname" 12
The canonical for the source.
.IP "ai_dst_canonname" 12
The canonical for the destination.
.IP "ai_route_len" 12
Size of the routing information buffer referenced by ai_route.  This will
be 0 if the underlying transport does not require routing data, or none 
could be resolved.
.IP "ai_route" 12
Routing information for RDMA transports that require routing data as part
of connection establishment.  The format of the routing data depends on
the underlying transport.  If Infiniband transports are
used, ai_route will reference an array of struct ibv_path_data on output,
if routing data is available.  Routing paths may be restricted by setting
desired routing data fields on input to rdma_getaddrinfo.  For Infiniband,
hints.ai_route may reference an array of struct ibv_path_record or
struct ibv_path_data on input.
.IP "ai_connect_len" 12
Size of connection information referenced by ai_connect.  This will be
0 if the underlying transport does not require additional connection
information.
.IP "ai_connect" 12
Data exchanged as part of the connection establishment process.  If provided,
ai_connect data must be transferred as private data, with any user supplied
private data following it.
.IP "ai_next" 12
Pointer to the next rdma_addrinfo structure in the list.  Will be NULL
if no more structures exist.
.SH "SEE ALSO"
rdma_create_id(3), rdma_resolve_route(3), rdma_connect(3), rdma_create_qp(3),
rdma_bind_addr(3), rdma_create_ep(3), rdma_freeaddrinfo(3)