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44 lines
1.4 KiB
44 lines
1.4 KiB
2 years ago
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## Input redirection
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### Instructions
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In this exercise you will make a script `input-redirection.sh`.
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This script will read from an here document (`HereDoc`).
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Usually this technique is used to programmatically generate scripts or configuration files receiving some multiline input.
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The script will create a file `show_info.sh` that will run the command `cat` with `-e` as argument.
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The input to `cat` will be passed using `HereDoc`. Running `show_info.sh` will output some useful information about three common environment variables.
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> The environment variables are `PWD`, `PATH` and `USERNAME`.
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### Usage
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- First generate the script programmatically:
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```console
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$ ./input_redirection.sh
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$
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```
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- Then run the generated script:
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```console
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$ ./show_info.sh
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The current directory is: current/path/example$
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The default paths are: /first_path:/second_path:/third_path$
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The current user is: your_name$
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$
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```
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### Hints
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You will need to mix more than one redirection tool:
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- `>` will be useful to create `show_info.sh`.
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- `<<` is the `HereDoc` redirection.
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- To start playing with `HereDoc` you can try `wc -l <<EOF`, type some random things, then write `EOF` on a new line and press `Enter`.
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- Don't forget you can use `echo` to write into `show_info.sh`.
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> You have to use Man or Google to know more about commands flags, in order to solve this exercise!
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> Google and Man will be your friends!
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