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BT_DEV(3)                  Library Functions Manual                  BT_DEV(3)

     bt_devaddr, bt_devname, bt_devenum, bt_devinfo, bt_devopen, bt_devsend,
     bt_devrecv, bt_devreq, bt_devfilter, bt_devfilter_pkt_set,
     bt_devfilter_pkt_clr, bt_devfilter_pkt_tst, bt_devfilter_evt_set,
     bt_devfilter_evt_clr, bt_devfilter_evt_tst, bt_devinquiry - Bluetooth
     device access routines

     Bluetooth Library (libbluetooth, -lbluetooth)

     #include <bluetooth.h>

     bt_devaddr(const char *name, bdaddr_t *bdaddr);

     bt_devname(char *name, const bdaddr_t *bdaddr);

     bt_devenum(int (*cb)(int, const struct bt_devinfo *, void *), void *arg);

     bt_devinfo(const char *name, struct bt_devinfo *info);

     bt_devopen(const char *name, int flags);

     bt_devsend(int s, uint16_t opcode, void *param, size_t plen);

     bt_devrecv(int s, void *buf, size_t size, time_t timeout);

     bt_devreq(int s, struct bt_devreq *req, time_t timeout);

     bt_devfilter(int s, const struct bt_devfilter *new,
         struct bt_devfilter *old);

     bt_devfilter_pkt_set(struct bt_devfilter *filter, uint8_t type);

     bt_devfilter_pkt_clr(struct bt_devfilter *filter, uint8_t type);

     bt_devfilter_pkt_tst(const struct bt_devfilter *filter, uint8_t type);

     bt_devfilter_evt_set(struct bt_devfilter *filter, uint8_t event);

     bt_devfilter_evt_clr(struct bt_devfilter *filter, uint8_t event);

     bt_devfilter_evt_tst(const struct bt_devfilter *filter, uint8_t event);

     bt_devinquiry(const char *name, time_t timeout, int max_rsp,
         struct bt_devinquiry **iip);

     These routines are designed to provide access to locally configured
     Bluetooth devices in an operating system independent manner via a socket
     providing access to Bluetooth HCI packets.

     bt_devaddr(name, bdaddr)
           Return a Bluetooth device address.  bt_devaddr() will return 1 if
           the NUL-terminated name string refers to a Bluetooth device present
           in the system, otherwise 0.  The name may be given as a device name
           (eg "ubt0") or Bluetooth device address (eg "00:11:22:33:44:55")
           and the actual device address will be written to bdaddr if not

     bt_devname(name, bdaddr)
           Return a Bluetooth device name.  bt_devname() returns 1 if the
           bdaddr refers to a Bluetooth device present in the system,
           otherwise 0.  The name buffer, if given, should have space for at
           least HCI_DEVNAME_SIZE bytes and the string will be NUL-terminated.

     bt_devenum(cb, arg)
           Enumerate Bluetooth devices present in the system.  For each device
           found, the cb function (if not NULL) will be called with the arg
           argument provided, a fully populated bt_devinfo structure and,
           where the device is enabled, a socket handle as returned by
           bt_devopen().  The callback function can halt the enumeration by
           returning a non-zero value, and bt_devenum() returns the number of
           successfully enumerated devices.

     bt_devinfo(name, info)
           Obtain information from a Bluetooth device present in the system.
           The info argument is a pointer to a bt_devinfo structure into which
           information about device name is placed.  The bt_devinfo structure
           contains at least the following members:

                   char        devname[HCI_DEVNAME_SIZE];
                   int         enabled;    /* device is enabled */

                   /* device information */
                   bdaddr_t    bdaddr;
                   uint8_t     features[HCI_FEATURES_SIZE];
                   uint16_t    acl_size;   /* max ACL data size */
                   uint16_t    acl_pkts;   /* total ACL packet buffers */
                   uint16_t    sco_size;   /* max SCO data size */
                   uint16_t    sco_pkts;   /* total SCO packet buffers */

                   /* flow control */
                   uint16_t    cmd_free;   /* available CMD packet buffers */
                   uint16_t    acl_free;   /* available ACL packet buffers */
                   uint16_t    sco_free;   /* available SCO packet buffers */

                   /* statistics */
                   uint32_t    cmd_sent;
                   uint32_t    evnt_recv;
                   uint32_t    acl_recv;
                   uint32_t    acl_sent;
                   uint32_t    sco_recv;
                   uint32_t    sco_sent;
                   uint32_t    bytes_recv;
                   uint32_t    bytes_sent;

                   /* device settings */
                   uint16_t    link_policy_info;
                   uint16_t    packet_type_info;
                   uint16_t    role_switch_info;

           Because a Bluetooth device must be enabled in order to retrieve
           information, the enabled flag should be tested to be non-zero
           before relying on further data.

     bt_devopen(name, flags)
           Return a Bluetooth HCI socket handle bound and connected to the
           named Bluetooth device or, if name is NULL, enabled to receive
           packets from any device.  The socket should be closed using
           close(2) after use.  Any combination of the following flags may be
           used to pre-set the socket options:

           BTOPT_DIRECTION      Enable control messages on each packet
                                indicating the direction of travel.

           BTOPT_TIMESTAMP      Enable control messages providing packet

           The default filter on the socket will only allow the HCI Event
           packets "Command Status" and "Command Complete" to be received.

     bt_devsend(s, opcode, param, plen)
           Send an HCI command packet on the socket s.  The opcode should be
           in host byte order and the param and plen arguments can be used to
           provide command parameter data.  bt_devsend() will return the
           number of bytes successfully written.

     bt_devrecv(s, buf, size, timeout)
           Receive a single HCI packet on the socket s.  bt_devrecv() will
           return the number of bytes successfully received unless the
           provided buffer could not contain the entire packet, or if a
           timeout was requested with a non-negative timeout value.

     bt_devreq(s, req, timeout)
           Make an HCI request on the socket s.  The req argument is a pointer
           to a bt_devreq structure, defined as:

                 struct bt_devreq {
                         uint16_t        opcode;
                         uint8_t         event;
                         void           *cparam;
                         size_t          clen;
                         void           *rparam;
                         size_t          rlen;

           bt_devreq() sends an HCI command packet with the given opcode and
           command parameters of clen bytes at cparam then waits up to timeout
           seconds for the command to return a "Command Complete" event.  In
           the case where the command returns "Command Status" and an
           additional event, and where the status indicates that the command
           is in progress, bt_devreq() will wait for the additional event
           specified in the request.  If required, any response will be copied
           into the buffer of rlen bytes at rparam, and rlen will be adjusted
           to indicate the number of bytes stored.  bt_devreq() temporarily
           modifies the socket filter.

     bt_devfilter(s, new, old)
           Update or extract the packet filter on HCI socket s.  Filters can
           be set to indicate packet types (Commands, Events, ACL and SCO
           data), and individual event IDs.  Where old is given, the currently
           set filter will be extracted first, then if new is given, the
           filter will be updated.

     bt_devfilter_pkt_set(filter, type)
           Set packet type in filter.

     bt_devfilter_pkt_clr(filter, type)
           Clear packet type from filter.

     bt_devfilter_pkt_tst(filter, type)
           Test if filter has packet type set.

     bt_devfilter_evt_set(filter, event)
           Set event ID in filter.

     bt_devfilter_evt_clr(filter, event)
           Clear event ID from filter.

     bt_devfilter_evt_tst(filter, event)
           Test if filter has event ID set.

     bt_devinquiry(name, timeout, max_rsp, iip)
           Perform a Bluetooth Inquiry using the device name, or the first
           available device if NULL is passed.  The inquiry length will be
           timeout seconds, and the number of responses (up to a limit of
           max_rsp) will be returned.  A pointer to an array of bt_devinquiry
           structures, defined as:

                 struct bt_devinquiry {
                         bdaddr_t        bdaddr;
                         uint8_t         pscan_rep_mode;
                         uint8_t         pscan_period_mode;
                         uint8_t         dev_class[3];
                         uint16_t        clock_offset;
                         int8_t          rssi;
                         uint8_t         data[240];

           will be stored in the location given by iip and this should be
           released after use with free(3).

     These Bluetooth device access routines return -1 on failure, and errno
     will be set to indicate the error.

     In addition to errors returned by the standard C library IO functions,
     the following errors may be indicated by device access routines.

           [EINVAL]          A provided function argument was not valid.

           [EIO]             A device response was not properly understood.

           [ETIMEDOUT]       An operation exceeded the given time limit.


     The Bluetooth device access API was created by Maksim Yevmenkin and first
     appeared in FreeBSD.  This implementation written for NetBSD by Iain

NetBSD 10.99                   October 25, 2011                   NetBSD 10.99