mirror of https://github.com/01-edu/public.git
eslopfer
2 years ago
1 changed files with 43 additions and 0 deletions
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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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