# Basic
查看命令类型: type 'cmd'
查看系统： cat /etc/os-release
man
tldr: https://tldr.sh/
npm install -g tldr
或者
pip install tldr
cd /usr/bin
sudo ln -s /home/lyhistory/.local/bin/tldr tldr (/usr/bin/tldr)
或者修改.bashrc
export PATH=$PATH:$HOME/.local/bin
# File Operation
# vim
# transfer
include hidden file: add the dot in the ending
scp -rp src/. [email protected]:dest/
# files&directory
创建文件夹
install -d /path/to/targetfolder
# FIND
find . -size +1G -ls | sort -k7n
find / -type f -name "mysql-connector-java-5.1.24.jar" -print
find / -type f -name "Locations.xml" -print
# GREP/zgrep
https://www.cyberciti.biz/faq/howto-use-grep-command-in-linux-unix/
grep/zgrep "pattern" file/file.gz
grep -H -r "syscript" ~ | cut -d: -f1 | sort -u
grep -H -r "create_db.sh" ~ | cut -d: -f1 | sort -u
grep -H -r "/apps/lib" ~ | cut -d: -f1 | sort -u
# split
split -a 4 -d -l 20000 2021-02-15_test.log ./test/test_
# du/df
由一次磁盘告警引发的血案 | 你知道 du 和 ls 区别吗？
https://mp.weixin.qq.com/s/BMeSEcQbhC4dcH-oYEtE-g
df -h
du -sh ./*
# crontab
/etc/crontab是系统级别的crontab，系统的设置
crontab -e是用户级的crontab
linux下实际保存在/var/spool/cron/username中
crontab是分用户的，默认为当前用户，可以通过-u指定用户
日志
/var/log/cron
/var/spool/mail/root
# history
#Delete your Linux history without leaving a trace!
history -d $((HISTCMD-1)) && history -d [line entry number]