Documentation/infiniband/user_mad.rst

48   buffer needed is set in mad.length.
52 	struct ib_user_mad *mad;
53 	mad = malloc(sizeof *mad + 256);
54 	ret = read(fd, mad, sizeof *mad + 256);
55 	if (ret != sizeof mad + 256) {
57 		free(mad);
62 	struct ib_user_mad *mad;
63 	mad = malloc(sizeof *mad + 256);
64 	ret = read(fd, mad, sizeof *mad + 256);
66 		length = mad.length;
67 		free(mad);
68 		mad = malloc(sizeof *mad + length);
69 		ret = read(fd, mad, sizeof *mad + length);
73 		free(mad);
78   example, the remote LID will be in mad.lid.
80   If a send times out, a receive will be generated with mad.status set
82   mad.status will be 0.
94 	struct ib_user_mad *mad;
96 	mad = malloc(sizeof *mad + mad_length);
98 	/* fill in mad->data */
100 	mad->hdr.id  = my_agent;	/* req.id from agent registration */
101 	mad->hdr.lid = my_dest;		/* in network byte order... */
104 	ret = write(fd, &mad, sizeof *mad + mad_length);
105 	if (ret != sizeof *mad + mad_length)