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On the command line, the - character is used to indicate a short form argument, which is a single-letter argument that can be specified using a single hyphen and the letter of the argument. For example, the -h argument is commonly used to show the help message for a command, and the -v argument is commonly used to enable verbose output. You can only use the single hyphen (-) when the argument consists of a single letter.
Examples where single hyphen can be used: -h, -Rand-f, but you can not use single hyphens for multi-letter arguments such as -verbose or -help.
The -- characters are used to indicate a long form argument, which is a multi-letter argument that can be specified using a double hyphen and the name of the argument. For example, the --help argument is commonly used to show the help message for a command, and the --verbose argument is commonly used to enable verbose output.
Examples where double hyphens can be used: --verbose, --server and --help, but you can’t use them for single-letter arguments like --h or --R
Examples of how to use single or double hyphens:
# Show the help message for a command using the -h short form argument my_command -h # Enable verbose output for a command using the --verbose long form argument my_command --verbose # Combine multiple arguments my_command --verbose --server https://techoverflow.net -f 0.1