LaunchDaemon无法找到bash命令问题排查求助

场景说明 #

我在MacBook上编写了一个bash脚本，用来根据WF-1000XM3蓝牙耳机的连接状态自动启用/禁用睡眠，实现合盖听歌时不受干扰。脚本存放于/Users/klumpy/Library/Scripts目录，由LaunchDaemon每5秒触发一次，依赖brew安装的blueutil命令。

原脚本内容 #

#!/usr/bin/env
export PATH=$(cat /Users/klumpy/Library/Scripts/PATH)
export BLUEUTIL_ALLOW_ROOT=1
# Check if "WF-1000XM3 is connected, if yes disable sleep, if not, don't go to sleep.
echo $(blueutil --connected)
echo $(blueutil --connected | grep "WF-1000XM3")
if [[ $(blueutil --connected | grep "WF-1000XM3" -c) -ne 0 ]]; then
  sudo pmset disablesleep 1
  echo "Sleep Disabled"
else
  sudo pmset disablesleep 0
  echo "Sleep Enabled"
fi

原LaunchDaemon plist文件内容 #

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
  <dict>
    <key>Label</key>
      <string>com.example.bluetoothsleep</string>
    <key>ProgramArguments</key>
    <array>
      <string>sudo</string>
      <string>bash</string>
      <string>/Users/klumpy/Library/Scripts/disablesleep</string>
    </array>
    <key>StandardErrorPath</key>
      <string>/Users/klumpy/Documents/Programming/bin/stderr.txt</string>
    <key>StandardOutPath</key>
      <string>/Users/klumpy/Documents/Programming/bin/stdout.txt</string>
    <key>StartInterval</key>
      <integer>5</integer>
  </dict>
</plist>

问题现象 #

• 脚本在终端运行完全正常，但LaunchDaemon触发时找不到blueutil命令；
• 最初打印$PATH仅得到/usr/bin:/bin:/usr/sbin:/sbin，将终端$PATH内容存入脚本同目录的PATH文件并导出后，脚本输出只剩“Sleep Enabled”，前两条echo无内容；
• 无论耳机是否连接，脚本始终走else分支，完全无法识别耳机状态。

错误原因及修复方案 #

1. 修复脚本shebang错误 #

原脚本第一行#!/usr/bin/env不完整，未指定具体shell，LaunchDaemon可能默认用sh执行，导致语法和环境差异。修改为：

#!/usr/bin/env bash

2. 直接指定blueutil绝对路径，避免PATH问题 #

brew安装的blueutil路径分两种：

• Apple Silicon Mac：/opt/homebrew/bin/blueutil
• Intel Mac：/usr/local/bin/blueutil

在脚本里直接用绝对路径调用，彻底规避PATH配置的坑：

# 根据自己的Mac架构选择路径
BLUEUTIL_PATH="/opt/homebrew/bin/blueutil"
# BLUEUTIL_PATH="/usr/local/bin/blueutil"

3. 移除LaunchDaemon中的冗余sudo #

LaunchDaemon本身以root身份运行，无需在ProgramArguments里加sudo——sudo会重置环境变量，导致之前配置的PATH失效。修改plist的ProgramArguments：

<key>ProgramArguments</key>
<array>
  <string>/bin/bash</string>
  <string>/Users/klumpy/Library/Scripts/disablesleep</string>
</array>

同时脚本里的sudo pmset也可以去掉sudo，root身份运行不需要额外授权。

4. 优化脚本逻辑，减少重复调用 #

原脚本重复执行blueutil --connected三次，既低效又可能导致状态不一致，改为先把结果存到变量里再复用：

connected_devices=$($BLUEUTIL_PATH --connected)
echo "$connected_devices"
echo "$connected_devices" | grep "WF-1000XM3"

if echo "$connected_devices" | grep -q "WF-1000XM3"; then

修复后的完整脚本 #

#!/usr/bin/env bash
# 根据Mac架构选择对应路径
BLUEUTIL_PATH="/opt/homebrew/bin/blueutil"
# BLUEUTIL_PATH="/usr/local/bin/blueutil"
export BLUEUTIL_ALLOW_ROOT=1

connected_devices=$($BLUEUTIL_PATH --connected)
echo "$connected_devices"
echo "$connected_devices" | grep "WF-1000XM3"

if echo "$connected_devices" | grep -q "WF-1000XM3"; then
  pmset disablesleep 1
  echo "Sleep Disabled"
else
  pmset disablesleep 0
  echo "Sleep Enabled"
fi

修复后的plist文件 #

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
  <dict>
    <key>Label</key>
      <string>com.example.bluetoothsleep</string>
    <key>ProgramArguments</key>
    <array>
      <string>/bin/bash</string>
      <string>/Users/klumpy/Library/Scripts/disablesleep</string>
    </array>
    <key>StandardErrorPath</key>
      <string>/Users/klumpy/Documents/Programming/bin/stderr.txt</string>
    <key>StandardOutPath</key>
      <string>/Users/klumpy/Documents/Programming/bin/stdout.txt</string>
    <key>StartInterval</key>
      <integer>5</integer>
  </dict>
</plist>

内容的提问来源于stack exchange，提问作者Klumpy7