78 lines
1.3 KiB
Markdown
78 lines
1.3 KiB
Markdown
# 🧮 Bash Variables
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In **Bash scripting**, **variables** are used to store values like text or numbers. They allow scripts to be dynamic and reusable.
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---
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## ✍️ Defining Variables
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Variables are created **without spaces** around the `=` sign:
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```bash
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user="ali"
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age=21
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```
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* `user` is assigned the value `"ali"`.
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* `age` is assigned the value `21`.
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> ✅ Tip: No `let` or `var` is needed like in other programming languages.
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---
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## 📢 Using Variables
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You can **access variables** by prefixing them with `$`:
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```bash
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user="radin"
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echo "Welcome, $user"
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```
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**Output:**
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```
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Welcome, radin
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```
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---
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## 🧪 Full Script Example
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Here's a complete Bash script using variables:
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```bash
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#!/bin/bash
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user="mmd"
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age=25
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echo "$user is $age years old."
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```
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**Output:**
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```
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mmd is 25 years old.
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```
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---
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## 📌 Notes
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* Variable names are **case-sensitive** (`User` and `user` are different).
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* Avoid spaces around `=` when assigning.
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* Enclose variable values in quotes if they contain spaces.
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---
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## ✅ Summary
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| Task | Syntax |
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| --------------- | ---------------------------- |
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| Define variable | `name="value"` |
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| Use variable | `$name` |
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| Print value | `echo "$name"` |
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| With script | Use `#!/bin/bash` at the top |
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