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Top Forums Programming Declare member of struct as a pointer in c Post 302714141 by jim mcnamara on Thursday 11th of October 2012 09:19:37 PM
Old 10-11-2012
When you send a pointer you are NOT sending data. You are sending an address.
Code:
typedef 
 struct fulMsg { 
int msgType; 
int msgCount; 
uint8_t  *CC;
} fulMsg_t;

You are passing a reference, not the string of characters or binary data array you are pointing to. The reference on the other node is pointing to nothing. That is why you segfault. Unless your method is smart enough to create storage on the remote side and copy the array over there.
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UMAD_SET_GRH(3) 					    OpenIB Programmer's Manual						   UMAD_SET_GRH(3)

NAME
umad_set_grh - set GRH fields within umad buffer using host ordering SYNOPSIS
#include <infiniband/umad.h> int umad_set_grh(void *umad, void *mad_addr); DESCRIPTION
umad_set_grh() sets the GRH fields (grh_present, gid, hop_limit, traffic_class, flow_label) within the specified umad buffer based on the mad_addr supplied. The provided mad_addr fields are expected to be in host order. If the mad_addr pointer supplied is NULL, no GRH is set. The argument mad_addr is a pointer to an ib_mad_addr_t struct, as specified in <infiniband/umad.h>. The argument umad is a pointer to an ib_user_mad_t struct, as specified in <infiniband/umad.h>. typedef struct ib_mad_addr { uint32_t qpn; uint32_t qkey; uint16_t lid; uint8_t sl; uint8_t path_bits; uint8_t grh_present; uint8_t gid_index; uint8_t hop_limit; uint8_t traffic_class; uint8_t gid[16]; uint32_t flow_label; } ib_mad_addr_t; typedef struct ib_user_mad { uint32_t agent_id; uint32_t status; uint32_t timeout_ms; uint32_t retries; uint32_t length; ib_mad_addr_t addr; uint8_t data[0]; } ib_user_mad_t; RETURN VALUE
umad_set_grh() returns 0 on success, and a negative value on errors. Currently, there are no errors indicated. SEE ALSO
umad_set_grh_net(3) AUTHOR
Hal Rosenstock <halr@voltaire.com> OpenIB May 24, 2007 UMAD_SET_GRH(3)
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