NAME¶
cpg_mcast_joined - Multicasts to all groups joined to a handle
SYNOPSIS¶
#include <sys/uio.h> #include <corosync/cpg.h>
int cpg_mcast_joined(cpg_handle_t handle, cpg_guarantee_t
guarantee, struct iovec *iovec, int
iov_len);
DESCRIPTION¶
The
cpg_mcast_joined function will multicast a message to all the
processes that have been joined with the
cpg_join(3) function for the
same group name. Messages that are sent to any of the groups joined to the
parameter
handle will be delivered to all subscribed processes in the
system.
The argument
guarantee requests a delivery guarantee for the message to
be sent. The cpg_guarantee_t type is defined by:
typedef enum {
CPG_TYPE_UNORDERED, /* not implemented */
CPG_TYPE_FIFO, /* same as agreed */
CPG_TYPE_AGREED, /* implemented */
CPG_TYPE_SAFE /* not implemented */
} cpg_guarantee_t;
The meanings of the cpg_guarantee_t typedef are:
- CPG_TYPE_UNORDERED
- Messages are guaranteed to be delivered, but with no particular order.
This mode is unimplemented in the CPG library.
- CPG_TYPE_FIFO
- Messages are guaranteed to be delivered in first sent first delivery
order. In fact, this guarantee is equivalent to the CPG_TYPE_AGREED
guarantee.
- CPG_TYPE_AGREED
- All processors must agree on the order of delivery. If a message is sent
from two or more processes at about the same time, the delivery will occur
in the same order to all processes.
- CPG_TYPE_SAFE
- All processes must agree on the order of delivery. Further all processes
must have a copy of the message before any delivery takes place. This mode
is unimplemented in the CPG library.
The
iovec argument describes the scatter/gather list which is used to
transmit a message. This is a iovec described by:
struct iovec
{
void *iov_base; /* Pointer to data. */
unsigned int iov_len; /* Length of data. */
};
The
iov_len argument describes the number of entires in the
iovec
argument.
RETURN VALUE¶
This call returns the CPG_OK value if successful, otherwise an error is
returned.
ERRORS¶
The errors are undocumented.
SEE ALSO¶
cpg_overview(8),
cpg_initialize(3),
cpg_finalize(3),
cpg_fd_get(3),
cpg_dispatch(3),
cpg_join(3),
cpg_leave(3),
cpg_mcast_joined(3),
cpg_membership_get(3)
cpg_zcb_alloc(3) cpg_zcb_free(3) cpg_zcb_mcast_joined(3)
cpg_context_get(3) cpg_context_set(3) cpg_local_get(3)