awk, sed, xargs, bash

awk:

split($1, arr, “\t”)

sed:

sed -n '42p' file

sed '42d' file

sed 's/replace_pattern/replace_str/g' file

sed '/remove_pattern/d' file

sed -i file #(inplace)直接修改读取的文件内容，而不是输出到终端

xargs:

xargs -n1 -i cmd {}

bash:

$HOSTNAME - The hostname of the machine the script is running on.
Single quotes will treat every character literally.
Double quotes will allow you to do substitution (that is include variables within the setting of the value).
read varNameRead input from the user and store it in the variable varName./dev/stdinA file you can read to get the STDIN for the Bash script
$(( expression )) Return the result of the expression. ${#var} Return the length of the variable var.

巴特西