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e380f4eeb5
I realise it's a built-in, and that its operation can wildly differ, depending on the shell used, which is why I've added that the sheet is for the Bash built-in. I'm not sure how this project handles multiple different tools by the same name; worth looking into, @chubin?
30 lines
1.3 KiB
Plaintext
30 lines
1.3 KiB
Plaintext
# read (The Bash Built-in)
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# Read a line from the standard input and split it into fields
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# Standard approach to prompting the user for a single-character response, such
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# as a simple 'Y' or 'N' response. Using Bash's `read`, you can save time and
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# lines by having the prompt taken care of by `read` itself.
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#
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# The use of the `-e` flag tells read to return a new line afterwards. As the
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# `help read` output says:
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#
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# use Readline to obtain the line in an interactive shell
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#
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# Because we're using the `-n 1` flag and argument, we'll want `-e`, as the
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# user will not get a chance to press the Enter or Return key which would
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# otherwise give us that new line.
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read -n 1 -e -p 'Prompt: '
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# A while read loop in Bash is easily one of the best features, when properly
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# utilized; it often makes the use of tools like grep(1), sed(1), and even
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# awk(1) redundant, depending on the functionality required. This can offer
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# more efficiency, depending on what's needed and the amount of data to parse.
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#
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# In this example, the [I]nput [F]ield [S]eperator is set to `=` for only the
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# `read` built-in, and the `-a` flag is used to split the input, per the
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# provided IFS, into an array. This then means the first index is the key and
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# the second index the value, which is ideal when parsing configurtion files.
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while IFS='=' read -a Line; do
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COMMANDS
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done < INPUT_FILE
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