shell tips

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# C style
for ((i=1;i<=10;i++));
	do echo i;
done
# Use `seq`
for i in $(seq 10);
	do echo i;
done

# File
for i in /home/*.sh; do

# num
for i in {1..10}; do

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v=hello
a=${v#v=}
echo a	# hello

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# 会提示没有权限，因为 `>` 也是一个命令，`sudo`只能给一个命令权限
sudo echo 1 > /root/some/thing
# 改用tee
echo 1 | sudo tee /root/some/thing