bash-2.05$ touch aaa
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bash-2.05$ touch aaa bbb ccc
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bash-2.05$ tee welcome
hello i`m the welcome file
hello i`m the welcome file
i hope you get idea about Unix OS
i hope you get good  idea about Unix OS
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bash-2.05$ mkdir moqtel
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bash-2.05$mkdir the-one existenz welcome
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bash-2.05$mkdir -p lessons/les1/les2/les3