Moving back and forth between dierctorys in AWK

In AWK,开发者_运维知识库 how can I move back and forth between directories using “cd” command?

To illustarte what I am looking for, here is a small senario:

If a root directory includes subdirectory called subD. Now, assume that I have the awk srcipt code '*.awk' in the root directory, and I would the awk program to move to the subdirectory "subD", run a program, and return back to root directory.

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Use the absolute path to the files that you're reading so you don't need to change the current working directory inside your code.

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Usually it is better to put only text processing logic to awk code, and things like directory traversal in shell script calling that awk code.

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Use system(cmd) to run the external command cmd.