afreerunner

When crontab gives fopen: permission denied error

While trying to open my user's crontab on Ubuntu, the system barked back:

$ crontab -l
crontabs/myuser/: fopen: Permission denied

This is due to improper permissions on crontab executable.

title	subtitle	author	date	source
Docker Compose Cheatsheet	Quick reference for Docker Compose commands and config files	Jon LaBelle	April 7, 2019	https://jonlabelle.com/snippets/view/markdown/docker-compose-cheatsheet

	# I want to sync the local clock but don't have access to any NTP server.
	# Website https://time.is tells me the time difference of my system clock and I can manually adjust the local clock.

	# But then I recall that a HTTP response often contains a date header with current time in GMT timezone.
	# I'll use it to set the system clock with the precision of 1 or 2 seconds.
	# When I need more accurate time, I can use `datetime` (or `utc_datetime`) from `http://worldtimeapi.org/api/ip.txt`

	# time from worldtimeapi.org has millisecond precision, you can use it to compare with your system time:
	date -uIns && time curl -s http://worldtimeapi.org/api/ip.txt \| sed -n 's/^utc_datetime://p'
	date -Ins && time curl -s http://worldtimeapi.org/api/ip.txt \| sed -n 's/^datetime://p'

	import asyncio
	import json
	import logging
	import websockets
	import aioredis

	logging.basicConfig(level=logging.INFO)

	# STATE = {'value': 0}
	USERS = set()

	version: '3.1'

	services:

	db:
	image: mariadb
	restart: always
	command: mysqld --character-set-server=utf8 --collation-server=utf8_unicode_ci --init-connect='SET NAMES UTF8;' --innodb-flush-log-at-trx-commit=0
	ports:
	- 3306:3306

	FROM golang:1.9

	WORKDIR /go/src/github.com/purplebooth/example
	COPY . .
	RUN go build -ldflags "-linkmode external -extldflags -static" -a main.go

	FROM scratch
	COPY --from=0 /go/src/github.com/purplebooth/example/main /main
	CMD ["/main"]

	RUN apt update
	RUN apt upgrade -y
	RUN apt install -y apt-utils
	RUN a2enmod rewrite
	RUN apt install -y libmcrypt-dev
	RUN docker-php-ext-install mcrypt
	RUN apt install -y libicu-dev
	RUN docker-php-ext-install -j$(nproc) intl
	RUN apt-get install -y libfreetype6-dev libjpeg62-turbo-dev libpng12-dev
	RUN docker-php-ext-configure gd --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/

	#!/bin/sh

	# Convert rtsp stream to hls and write to file
	ffmpeg -i "rtsp://admin:[email protected]:554/cam/realmonitor?channel=1&subtype=0" -c copy -hls_time 2 -hls_wrap 10 "/var/www/html/streaming.m3u8"

	import time
	import socket
	import threading
	import logging

	from ws4py.client import WebSocketBaseClient
	from ws4py.streaming import Stream

	logger = logging.getLogger(__name__)

	# AES helper class for pycrypto
	# Copyright (c) Dennis Lee
	# Date 22 Mar 2017

	# Description:
	# Python helper class to perform AES encryption, decryption with CBC Mode & PKCS7 Padding

	# References:
	# https://www.dlitz.net/software/pycrypto/api/2.6/
	# http://japrogbits.blogspot.my/2011/02/using-encrypted-data-between-python-and.html