di_drv_first_node(3devinfo)

1di_child_node(3DEVINFOD)evice Information Library Functiondsi_child_node(3DEVINFO)
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NAME

6       di_child_node,   di_parent_node,   di_sibling_node,  di_drv_first_node,
7       di_drv_next_node - libdevinfo node traversal functions
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SYNOPSIS

10       cc [ flag... ] file... -ldevinfo [ library... ]
11       #include <libdevinfo.h>
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13       di_node_t di_child_node(di_node_t node);
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16       di_node_t di_parent_node(di_node_t node);
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19       di_node_t di_sibling_node(di_node_t node);
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22       di_node_t di_drv_first_node(const char *drv_name, di_node_t root);
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25       di_node_t di_drv_next_node(di_node_t node);
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PARAMETERS

29       drv_name    The name of the driver of interest.
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32       node        A  handle to any node in the snapshot.
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35       root        The handle of the root node for the  snapshot  returned  by
36                   di_init(3DEVINFO).
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DESCRIPTION

40       The  kernel device configuration data may be viewed in two ways, either
41       as a tree of device  configuration nodes or as a  list of nodes associ‐
42       ated  with  each driver. In the tree view, each node may contain refer‐
43       ences to  its parent, the next sibling in a list of siblings,  and  the
44       first  child  of  a list of children. In the per-driver view, each node
45       contains a reference to the next node associated with the same  driver.
46       Both  views  are  captured in the snapshot, and the interfaces are pro‐
47       vided for node  access.
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50       The di_child_node() function obtains a handle to  the  first  child  of
51       node.  If no child node exists in the snapshot, DI_NODE_NIL is returned
52       and errno is set to ENXIO or ENOTSUP.
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55       The di_parent_node() function obtains a handle to the  parent  node  of
56       node. If no parent node exists in the snapshot, DI_NODE_NIL is returned
57       and errno is set to ENXIO or ENOTSUP.
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60       The di_sibling_node() function obtains a handle  to  the  next  sibling
61       node  of  node.  If  no  next  sibling   node  exists  in the snapshot,
62       DI_NODE_NIL is returned and errno is set to ENXIO or ENOTSUP.
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65       The di_drv_first_node() function obtains a handle  to  the  first  node
66       associated  with  the driver specified by drv_name. If there is no such
67       driver, DI_NODE_NIL is returned with errno is set  to  EINVAL.  If  the
68       driver  exists  but  there  is  no  node  associated  with this driver,
69       DI_NODE_NIL is  returned and errno is set to ENXIO or ENOTSUP.
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72       The di_drv_next_node() function returns a handle to the next node bound
73       to the same driver. If no more nodes exist, DI_NODE_NIL is returned.
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RETURN VALUES

76       Upon   successful   completion,   a   handle  is  returned.  Otherwise,
77       DI_NODE_NIL is returned and errno is set to indicate the error.
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ERRORS

80       These functions will fail if:
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82       EINVAL     The argument is invalid.
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85       ENXIO      The requested node does not exist.
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88       ENOTSUP    The node was not found in the snapshot, but it may exist  in
89                  the  kernel. This error may occur if the snapshot contains a
90                  partial device tree.
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ATTRIBUTES

94       See attributes(5)  for descriptions of the following attributes:
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99       ┌─────────────────────────────┬─────────────────────────────┐
100       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
101       ├─────────────────────────────┼─────────────────────────────┤
102       │Interface Stability          │Evolving                     │
103       ├─────────────────────────────┼─────────────────────────────┤
104       │MT-Level                     │Safe                         │
105       └─────────────────────────────┴─────────────────────────────┘
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