UMAD_RECV(3)						    OpenIB Programmer's Manual						      UMAD_RECV(3)

NAME

       umad_recv - receive umad

SYNOPSIS

       #include <infiniband/umad.h>

       int umad_recv(int portid, void *umad, int *length, int timeout_ms);

DESCRIPTION

       umad_recv() waits up to timeout_ms milliseconds for a packet to be received from the port specified by portid.  The packet is copied to the
       umad buffer if there is sufficient room and the received length is indicated.  If the buffer is not large enough, the size of the umad buf-
       fer  needed  is	returned  in length.  A negative timeout_ms makes the function block until a packet is received. A timeout_ms parameter of
       zero indicates a non blocking read.

       Note length is a pointer to the length of the data portion of the umad buffer.  This means that umad  must  point  to  a  buffer  at  least
       umad_size() + *length bytes long.

       Note also that *length must be >= 256 bytes.

RETURN VALUE

       umad_recv() returns non negative receiving agentid on success, and a negative value on error as follows:
	-EINVAL      invalid port handle or agentid or *length is less than the minimum supported
	-EIO	     receive operation failed
	-EWOULDBLOCK non blocking read can't be fulfilled

SEE ALSO

       umad_poll(3)

AUTHOR

       Hal Rosenstock <halr@voltaire.com>

OpenIB								   May 11, 2007 						      UMAD_RECV(3)