Tips in Linux

概览:

Clear apt cache

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sudo rm -v /var/cache/apt/archives/*.deb

镜像源公钥安装

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sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys # + 公钥名

获取CPU总核心数

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echo $(grep -c ^processor /proc/cpuinfo 2>/dev/null)
# use
make -j $(grep -c ^processor /proc/cpuinfo 2>/dev/null)

Linux Console 默认信息

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/etc/issue
/etc/update-motd.d/*
/run/motd.dynamic

shell script check permission

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if [ $(id -u) -ne 0 ]; then
printf "Script must be run as root\n"
exit 1
fi

Makefile help menu

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all: help

.PHONY: help
help: ## Show this help.
@fgrep -h "##" $(MAKEFILE_LIST) | fgrep -v fgrep | sed -e 's/\\$$//' | sed -e 's/##//'