| .\" Licensed under the OpenIB.org BSD license (FreeBSD Variant) - See COPYING.md |
| .TH "RDMA_CREATE_ID" 3 "2010-07-19" "librdmacm" "Librdmacm Programmer's Manual" librdmacm |
| .SH NAME |
| rdma_create_id \- Allocate a communication identifier. |
| .SH SYNOPSIS |
| .B "#include <rdma/rdma_cma.h>" |
| .P |
| .B "int" rdma_create_id |
| .BI "(struct rdma_event_channel *" channel "," |
| .BI "struct rdma_cm_id **" id "," |
| .BI "void *" context "," |
| .BI "enum rdma_port_space " ps ");" |
| .SH ARGUMENTS |
| .IP "channel" 12 |
| The communication channel that events associated with the |
| allocated rdma_cm_id will be reported on. This may be NULL. |
| .IP "id" 12 |
| A reference where the allocated communication identifier will be |
| returned. |
| .IP "context" 12 |
| User specified context associated with the rdma_cm_id. |
| .IP "ps" 12 |
| RDMA port space. |
| .SH "DESCRIPTION" |
| Creates an identifier that is used to track communication information. |
| .SH "RETURN VALUE" |
| Returns 0 on success, or -1 on error. If an error occurs, errno will be |
| set to indicate the failure reason. |
| .SH "NOTES" |
| Rdma_cm_id's are conceptually equivalent to a socket for RDMA |
| communication. The difference is that RDMA communication requires |
| explicitly binding to a specified RDMA device before communication |
| can occur, and most operations are asynchronous in nature. Asynchronous |
| communication events on an rdma_cm_id are reported through the associated |
| event channel. If the channel parameter is NULL, the rdma_cm_id will |
| be placed into synchronous operation. While operating synchronously, |
| calls that result in an event will block until the operation completes. |
| The event will be returned to the user through the rdma_cm_id structure, |
| and be available for access until another rdma_cm call is made. |
| .P |
| Users must release the rdma_cm_id by calling rdma_destroy_id. |
| .SH "PORT SPACE" |
| Details of the services provided by the different port spaces are outlined |
| below. |
| .IP RDMA_PS_TCP |
| Provides reliable, connection-oriented QP communication. Unlike TCP, the RDMA |
| port space provides message, not stream, based communication. |
| .IP RDMA_PS_UDP |
| Provides unreliable, connectionless QP communication. Supports both datagram |
| and multicast communication. |
| .IP RDMA_PS_IB |
| Provides for any IB services (UD, UC, RC, XRC, etc.). |
| .SH "SEE ALSO" |
| rdma_cm(7), rdma_create_event_channel(3), rdma_destroy_id(3), rdma_get_devices(3), |
| rdma_bind_addr(3), rdma_resolve_addr(3), rdma_connect(3), rdma_listen(3), |
| rdma_set_option(3) |
