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44 lines
982 B
44 lines
982 B
2 years ago
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## plus
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### Instructions
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In this exercise, you will make a script that will take two arguments from the command line, add them and output the result.
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### Usage
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```console
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$ ./plus.sh 2 3 | cat -e
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5$
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$
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```
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### Hints
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Here are some commands that you can combine to find the solution:
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- `expr`: this command evaluates an expression and outputs the result.
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- `command substitution - $(...)`: this command can be used to interpolate the output of running a command into a string. You can replace the ellipsis with your command.
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You could use `expr` like this:
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```console
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$ expr 2 - 2
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0$
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$
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```
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And `$(...)` like this:
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```console
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$ echo "This is the content of a file: $(cat file.txt)"
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This is the content of a file: <content of the file>`
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$
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```
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### Notions
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- [expr](https://www.gnu.org/software/coreutils/manual/html_node/expr-invocation.html#expr-invocation).
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- [command substitution](https://www.gnu.org/savannah-checkouts/gnu/bash/manual/bash.html#Command-Substitution).
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