将ATTR {idVendor}作为udev脚本中的参数传递

Question

我有一个脚本，只要连接了供应商1004的USB设备，就会运行该脚本。我正在使用的udev规则工作，看起来像这样。现在

SUBSYSTEM=="usb", ATTR{idVendor}=="1004", RUN+="/var/www/beta/trigger.php" 

我想有每当任何USB设备连接该脚本运行，并通过供应商ID作为参数。 （所以该脚本可以决定是否有要运行与否。）

添加可在脚本访问迄今的工作参数：

SUBSYSTEM=="usb", RUN+="/var/www/beta/trigger.php myparam" 

有人能告诉我如何更换“myparam”的值为ATTR {idVendor}？我尝试了各种组合，但我从来没有得到预期的结果...

非常感谢！

Answer 1

udev为您设置了几个可以使用的环境变量，其中包括ID_VENDOR。试试这个小脚本：

#!/bin/bash 

echo "Called by udev" >> /tmp/testenv 
env >> /tmp/testenv 
echo "Vendor id is $ID_VENDOR" >> /tmp/testenv 

把它放在一个规则中，你会看到为你设置了多少东西。

Answer 2

只是添加到这个答案，udev也可以让你传递参数RUN和PROGRAM。

从udev的手册页：

The NAME, SYMLINK, PROGRAM, OWNER, GROUP, MODE and RUN fields support simple 
    printf-like string substitutions. The RUN format chars gets applied after 
    all rules have been processed, right before the program is executed. It 
    allows the use of device properties set by earlier matching rules. For all 
    other fields, substitutions are applied while the individual rule is being 
    processed. 

例如，你可以有这样的规则：

# Passes major, minor and serial number as parameters to script. 
ACTION=="add", SUBSYSTEM=="usb", RUN+="/tmp/test.sh %M %m $attr{serial}" 

可用替换：

$kernel, %k 
     The kernel name for this device. 

    $number, %n 
     The kernel number for this device. For example, ´sda3´ has kernel number 
     of ´3´ 

    $devpath, %p 
     The devpath of the device. 

    $id, %b 
     The name of the device matched while searching the devpath upwards for 
     SUBSYSTEMS, KERNELS, DRIVERS and ATTRS. 

    $driver 
     The driver name of the device matched while searching the devpath 
     upwards for SUBSYSTEMS, KERNELS, DRIVERS and ATTRS. 

    $attr{file}, %s{file} 
     The value of a sysfs attribute found at the device, where all keys of 
     the rule have matched. If the matching device does not have such an 
     attribute, follow the chain of parent devices and use the value of the 
     first attribute that matches. If the attribute is a symlink, the last 
     element of the symlink target is returned as the value. 

    $env{key}, %E{key} 
     A device property value. 

    $major, %M 
     The kernel major number for the device. 

    $minor, %m 
     The kernel minor number for the device. 

    $result, %c 
     The string returned by the external program requested with PROGRAM. A 
     single part of the string, separated by a space character may be 
     selected by specifying the part number as an attribute: %c{N}. If 
     the number is followed by the ´+´ char this part plus all remaining 
     parts of the result string are substituted: %c{N+} 

    $parent, %P 
     The node name of the parent device. 

    $name 
     The current name of the device node. If not changed by a rule, it 
     is the name of the kernel device. 

    $links 
     The current list of symlinks, separated by a space character. The 
     value is only set if an earlier rule assigned a value, or during a 
     remove events. 

    $root, %r 
     The udev_root value. 

    $sys, %S 
     The sysfs mount point. 

    $tempnode, %N 
     The name of a created temporary device node to provide access to the 
     device from a external program before the real node is created. 

    %% 
     The ´%´ character itself. 

    $$ 
     The ´$´ character itself.