1EVS_MCAST_GROUPS(3)Corosync Cluster Engine Programmer's ManuaElVS_MCAST_GROUPS(3)
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6 evs_join - Multicast a message to selected groups
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9 #include <sys/uio.h> #include <corosync/evs.h>
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11 int evs_mcast_groups(evs_handle_t handle, evs_guraantee_t guarantee,
12 evs_group_t *groups, int group_entries, struct iovec *iovec, int
13 iov_len);
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16 The evs_mcast_groups(3) function multicasts a message to all the groups
17 specified in the arguemnt groups. Messages are delivered to all pro‐
18 cessors in the system that are described by the current configuration.
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20 The argument handle describes a handle created with evs_initialize(3).
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22 The argument guarantee requests a delivery guarantee for the message to
23 be sent. The evs_guarantee_t type is defined by:
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25 typedef enum {
26 EVS_TYPE_UNORDERED, /* not implemented */
27 EVS_TYPE_FIFO, /* same as agreed */
28 EVS_TYPE_AGREED, /* implemented */
29 EVS_TYPE_SAFE /* not implemented */
30 } evs_guarantee_t;
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32 The meanings of the evs_guarantee_t typedef are:
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34 EVS_GUARANTEE_UNORDERED
35 Messages are guaranteed to be delivered, but with no particular
36 order. This mode is unimplemented in the EVS library.
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38 EVS_GUARANTEE_FIFO
39 Messages are guaranteed to be delivered in first sent first
40 delivery order from one one. In fact, this guarantee is actu‐
41 ally the AGREED guarantee.
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43 EVS_GUARANTEE_AGREED
44 All processors must agree on the order of delivery. If a mes‐
45 sage is sent from two or more processors at about the same time,
46 the delivery will occur in the same order to all processors.
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48 EVS_GUARANTEE_SAFE
49 All processors must agree on the order of delivery. Further all
50 processors must have a copy of the message before any delivery
51 takes place. This mode is unimplemented in the EVS library.
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53 The groups argument is of the type evs_group_t which is defined by the
54 structure:
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57 typedef struct {
58 char key[32];
59 } evs_groups_t;
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61 The group_entries argument describes the number of entries in the group
62 argument.
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64 The iovec argument describes the scatter/gather list which is used to
65 transmit a message. This is a standard socket structure described by:
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67 struct iovec
68 {
69 void *iov_base; /* Pointer to data. */
70 unsigned int iov_len; /* Length of data. */
71 };
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73 The iovlen argument describes the number of entires in the iovec argu‐
74 ment.
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78 This call returns the EVS_OK value if successful, otherwise an error is
79 returned.
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82 The errors are undocumented.
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85 evs_overview(8), evs_initialize(3), evs_finalize(3), evs_fd_get(3),
86 evs_dispatch(3), evs_leave(3), evs_join(3), evs_mcast_joined(3),
87 evs_mmembership_get(3) evs_context_get(3) evs_context_set(3)
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89corosync Man Page 2004-08-31 EVS_MCAST_GROUPS(3)