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# Startup Commands

`cmd2` provides a couple different ways for running commands immediately after your application starts up:

1. Commands at Invocation
2. Startup Script

Commands run as part of a startup script are always run immediately after the application finishes initializing so they are guaranteed to run before any Commands At Invocation.

## Commands At Invocation

You can send commands to your app as you invoke it by including them as extra arguments to the program. `cmd2` interprets each argument as a separate command, so you should enclose each command in quotation marks if it is more than a one-word command. You can use either single or double quotes for this purpose.

    $ python examples/transcript_example.py "say hello" "say Gracie" quit
    hello
    Gracie

You can end your commands with a quit command so that your `cmd2` application runs like a non-interactive command-line utility (CLU). This means that it can then be scripted from an external application and easily used in automation.

Note

If you wish to disable cmd2's consumption of command-line arguments, you can do so by setting the `allow_cli_args` argument of your cmd2.Cmd class instance to `False`. This would be useful, for example, if you wish to use something like argparse to parse the overall command line arguments for your application:

    from cmd2 import Cmd
    class App(Cmd):
        def __init__(self):
            super().__init__(allow_cli_args=False)

## Startup Script

You can execute commands from an initialization script by passing a file path to the `startup_script` argument to the `cmd2.Cmd.__init__()` method like so:

    class StartupApp(cmd2.Cmd):
        def __init__(self):
            cmd2.Cmd.__init__(self, startup_script='.cmd2rc')

This text file should contain a Command Script. See the getting_started.py example for a demonstration.

You can silence a startup script's output by setting `silence_startup_script` to True:

    cmd2.Cmd.__init__(self, startup_script='.cmd2rc', silence_startup_script=True)

Warning

Anything written to `stderr` will still print for a "silenced" startup script. Additionally, a startup script cannot be silenced if `allow_redirection` is False since silencing works by redirecting a script's output to `os.devnull`.