Crontab @reboot 和 streamlink PATH 问题答案

【问题标题】：Crontab @reboot and streamlink PATH issuesCrontab @reboot 和 streamlink PATH 问题
【发布时间】：2021-06-29 20:52:55
【问题描述】：

我正在尝试使用我的树莓派在启动时运行 python3 脚本。 python 脚本包含一个给我带来问题的子进程调用。我怀疑这个问题与 streamlink 调用的路径有关，但我没有设法解决它。

脚本：

#!/usr/bin/env python3

import subprocess

def streamlistener(streamname):
        try:
                print('Listening to stream: ',streamname)
                grepOut = subprocess.check_output(['streamlink','-p','omxplayer','-a','--timeout 20', '--player-fifo','--retry-strea$
                print(grepOut.decode())
                streamlistener(streamname)
        except subprocess.CalledProcessError as e:
                print("ERRORS: " , e.output.decode())
                streamlistener(streamname)

streamlistener('STREAMNAME')

crontab（没有 sleep 命令的结果相同）：

@reboot sleep 60 && sudo python3 /home/pi/Desktop/stream.py 2>&1 | logger -p user.debug -t 'stream'

我得到的错误信息：

Jun 28 17:40:39 raspberrypi stream: Traceback (most recent call last):
Jun 28 17:40:39 raspberrypi stream:   File "/home/pi/Desktop/stream.py", line 26, in <module>
Jun 28 17:40:39 raspberrypi stream:     streamlistener('northernstreaming')
Jun 28 17:40:39 raspberrypi stream:   File "/home/pi/Desktop/stream.py", line 19, in streamlistener
Jun 28 17:40:39 raspberrypi stream:     grepOut = subprocess.check_output(['streamlink','-p','omxplayer','-a','--timeout 20', '--pla$
Jun 28 17:40:39 raspberrypi stream:   File "/usr/lib/python3.7/subprocess.py", line 395, in check_output
Jun 28 17:40:39 raspberrypi stream:     **kwargs).stdout
Jun 28 17:40:39 raspberrypi stream:   File "/usr/lib/python3.7/subprocess.py", line 472, in run
Jun 28 17:40:39 raspberrypi stream:     with Popen(*popenargs, **kwargs) as process:
Jun 28 17:40:39 raspberrypi stream:   File "/usr/lib/python3.7/subprocess.py", line 775, in __init__
Jun 28 17:40:39 raspberrypi stream:     restore_signals, start_new_session)
Jun 28 17:40:39 raspberrypi stream:   File "/usr/lib/python3.7/subprocess.py", line 1522, in _execute_child
Jun 28 17:40:39 raspberrypi stream:     raise child_exception_type(errno_num, err_msg, err_filename)
Jun 28 17:40:39 raspberrypi stream: FileNotFoundError: [Errno 2] No such file or directory: 'streamlink': 'streamlink'

【问题讨论】：

标签： python-3.x linux cron streamlink

【解决方案1】：

问题与用于安装 streamlink 的 PATH pip3 而不是 subprocess.check_output 调用有关，在 bashrc 和 crontab 的开头都正确设置了路径。

在bashrc中设置路径：https://linuxize.com/post/how-to-add-directory-to-path-in-linux/

在 cron 中设置路径：https://unix.stackexchange.com/questions/148133/how-to-set-crontab-path-variable

【讨论】：