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Syntax of a shell command
command-name [ -option(s) filename(s) or arguments ]
Everything in square brackets [] is optional.
Example: ls -l filename
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| * | An asterisk matches any number of characters in a filename, including none. |
| ? | The question mark matches any single character. |
| [ ] | Brackets enclose a set of characters, any one of which may match a single character at that position. |
| - | A hyphen used within [ ] denotes a range of characters. |
| ^ | Negates the sense of a match |
| ~ | A tilde at the beginning of a word expands to the name of your home directory. If you append another user's login name to the character, it refers to that user's home directory. |
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