Bluetooth 如何使用蓝牙CTL（如hcitool lescan）报告重复的接近信标

我可以使用hcitool lescan和--duplicates标志从附近的两个BLE设备捕获定期的LE广告报告（接近信标）：

$ sudo hcitool lescan --duplicates
LE Scan ...
C8:0F:10:29:4D:98 MI1S
C8:0F:10:29:4E:75 MI1S
C8:0F:10:29:4E:75 MI1S
C8:0F:10:29:4D:98 MI1S
C8:0F:10:29:4E:75 MI1S
C8:0F:10:29:4D:98 MI1S
<snip>

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您如何使用bluetoothctl从同一台设备捕获重复的LE广告报告，就像hcitool使用--duplicates选项一样？

我刚刚发现以下内容适用（Ubuntu 18.04.1，bluez 5.48）：

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似乎有一个默认的扫描过滤器处于活动状态，可以阻止大多数广告。

感谢Florian的建议

从我最初的帖子开始，我已经迁移到了Ubuntu 16.04.4嵌入式Linux发行版，其中包括Bluez5.42。不幸的是，此版本的bluetoothctl无法识别“菜单扫描”或“清除”：

[bluetooth]# menu scan
Invalid command

[bluetooth]# clear
Invalid command

然而，受您提到的“默认扫描过滤器处于活动状态，可阻止大多数广告”的鼓舞，我尝试了在我的bluetoothctl版本中可用的命令，如--help输出中所示，并取得了一些效果：

root@iot:~# bluetoothctl
[NEW] Controller 00:1A:7D:DA:71:13 iot #1 [default]
[NEW] Controller 70:2C:1F:31:F4:AF iot 

[bluetooth]# set-scan-filter-clear
SetDiscoveryFilter success

[bluetooth]# set-scan-filter-transport le
SetDiscoveryFilter success

[bluetooth]# scan on
Discovery started

[CHG] Controller 00:1A:7D:DA:71:13 Discovering: yes
[NEW] Device 0F:64:64:EE:E7:C4 0F-64-64-EE-E7-C4
[NEW] Device 0D:6F:45:77:87:F3 0D-6F-45-77-87-F3
[NEW] Device 40:CB:C0:F2:96:27 40-CB-C0-F2-96-27
[CHG] Device 0D:6F:45:77:87:F3 RSSI: -71
[CHG] Device FC:F1:36:73:77:B3 RSSI: -57
[CHG] Device 0F:64:64:EE:E7:C4 RSSI: -49

只需在bluetoothctl中键入一点就可以按照我想要的方式进行配置，而且在我们的信标丰富的环境中，bluetoothctl日志记录活动会很快使键入变得模糊。因此，我编写了一个bash脚本，它使用一个herdeoc，并希望将命令提供给bluetoothctl，sed/grep/perl对输出进行处理：

$ cat beacon-scan.sh 
#!/bin/bash

# beacon-scan.sh
# Displays beacons including duplicates in real time.
# Uses expect to automate interaction with bluetoothctl.
# Uses sed to remove bluetoothctl colorization escape characters.
# Uses grep to filter out beacon manufacturer data logging.
# Uses perl to prefix each beacon with a timestamp.

if [ "$(id -u)" != "0" ]; then
    echo "ERROR: must run as root"
    exit 1
fi

(cat <<'END' | /usr/bin/expect

    set prompt "#"
    set timeout -1

    spawn bluetoothctl

    expect -re $prompt
    send "scan off\r"

    expect -re $prompt
    send "remove *\r"

    expect -re $prompt
    send "set-scan-filter-clear\r"

    expect -re $prompt
    send "set-scan-filter-transport le\r"

    expect -re $prompt
    send "scan on\r"

    trap {
        expect -re $prompt
        send "scan off\r"

        expect -re $prompt
        send "remove *\r"

        expect -re $prompt
        send "quit\r"
    } SIGINT

    expect eof

END
) | sed --unbuffered --quiet --expression 's/^.*Device //p' \
  | grep --line-buffered -v ManufacturerData \
  | perl -nle 'print scalar(localtime), " ", $_'

bluetoothctl现在报告重复的信标，类似于使用duplicates标志运行hcitool lescan时

我要说的是，如果可以从命令行配置bluetoothctl，而不需要以交互方式进行配置，也不需要使用更复杂的脚本，那么bluetoothctl将更易于使用

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感谢Florian的帮助。

我很想知道为什么建议使用bluetoothctl，以及您是否能够使其正常工作。因为

bluetoothctl

通过DBus与蓝牙守护进程对话，而不是像

hcitool

那样直接与硬件对话。而hcitool现在通常会失败，因为BT守护进程具有独占访问权限。

[bluetooth]# menu scan
Invalid command

[bluetooth]# clear
Invalid command

root@iot:~# bluetoothctl
[NEW] Controller 00:1A:7D:DA:71:13 iot #1 [default]
[NEW] Controller 70:2C:1F:31:F4:AF iot 

[bluetooth]# set-scan-filter-clear
SetDiscoveryFilter success

[bluetooth]# set-scan-filter-transport le
SetDiscoveryFilter success

[bluetooth]# scan on
Discovery started

[CHG] Controller 00:1A:7D:DA:71:13 Discovering: yes
[NEW] Device 0F:64:64:EE:E7:C4 0F-64-64-EE-E7-C4
[NEW] Device 0D:6F:45:77:87:F3 0D-6F-45-77-87-F3
[NEW] Device 40:CB:C0:F2:96:27 40-CB-C0-F2-96-27
[CHG] Device 0D:6F:45:77:87:F3 RSSI: -71
[CHG] Device FC:F1:36:73:77:B3 RSSI: -57
[CHG] Device 0F:64:64:EE:E7:C4 RSSI: -49

$ cat beacon-scan.sh 
#!/bin/bash

# beacon-scan.sh
# Displays beacons including duplicates in real time.
# Uses expect to automate interaction with bluetoothctl.
# Uses sed to remove bluetoothctl colorization escape characters.
# Uses grep to filter out beacon manufacturer data logging.
# Uses perl to prefix each beacon with a timestamp.

if [ "$(id -u)" != "0" ]; then
    echo "ERROR: must run as root"
    exit 1
fi

(cat <<'END' | /usr/bin/expect

    set prompt "#"
    set timeout -1

    spawn bluetoothctl

    expect -re $prompt
    send "scan off\r"

    expect -re $prompt
    send "remove *\r"

    expect -re $prompt
    send "set-scan-filter-clear\r"

    expect -re $prompt
    send "set-scan-filter-transport le\r"

    expect -re $prompt
    send "scan on\r"

    trap {
        expect -re $prompt
        send "scan off\r"

        expect -re $prompt
        send "remove *\r"

        expect -re $prompt
        send "quit\r"
    } SIGINT

    expect eof

END
) | sed --unbuffered --quiet --expression 's/^.*Device //p' \
  | grep --line-buffered -v ManufacturerData \
  | perl -nle 'print scalar(localtime), " ", $_'

$ sudo ./beacon-scan.sh 
Wed Aug 22 19:34:07 2018 0F:64:64:EE:E7:C4 RSSI: -59
Wed Aug 22 19:34:07 2018 03:46:00:1D:E9:91 03-46-00-1D-E9-91
Wed Aug 22 19:34:07 2018 4E:20:6B:C7:68:D0 RSSI: -55
Wed Aug 22 19:34:07 2018 76:F1:1A:B9:ED:28 RSSI: -57
Wed Aug 22 19:34:07 2018 32:5D:8C:6A:72:C2 32-5D-8C-6A-72-C2
^C