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# Output Redirection and Pipes
As in POSIX shells, output of a command can be redirected and/or piped. This feature is fully cross-platform and works identically on Windows, macOS, and Linux.
## Output Redirection
### Redirect to a file
Redirecting the output of a `cmd2` command to a file works just like in POSIX shells:
- send to a file with `>`, as in `mycommand args > filename.txt`
- append to a file with `>>`, as in `mycommand args >> filename.txt`
If you need to include any of these redirection characters in your command, you can enclose them in quotation marks, `mycommand 'with > in the argument'`.
### Redirect to the clipboard
`cmd2` output redirection supports an additional feature not found in most shells - if the file name following the `>` or `>>` is left blank, then the output is redirected to the operating system clipboard so that it can then be pasted into another program.
- overwrite the clipboard with `mycommand args >`
- append to the clipboard with `mycommand args >>`
## Pipes
Piping the output of a `cmd2` command to a shell command works just like in POSIX shells:
- pipe as input to a shell command with `|`, as in `mycommand args | wc`
## Multiple Pipes and Redirection
Multiple pipes, optionally followed by a redirect, are supported. Thus, it is possible to do something like the following:
(Cmd) help | grep py | wc > output.txt
The above runs the **help** command, pipes its output to **grep** searching for any lines containing _py_, then pipes the output of grep to the **wc** "word count" command, and finally writes redirects the output of that to a file called _output.txt_.
## Disabling Redirection
!!! note
If you wish to disable cmd2's output redirection and pipes features, you can do so by setting the `allow_redirection` attribute of your `cmd2.Cmd` class instance to `False`. This would be useful, for example, if you want to restrict the ability for an end user to write to disk or interact with shell commands for security reasons:
```py
from cmd2 import Cmd
class App(Cmd):
def __init__(self):
super().__init__(allow_redirection=False)
```
cmd2's parser will still treat the `>`, `>>`, and `|` symbols as output redirection and pipe symbols and will strip arguments after them from the command line arguments accordingly. But output from a command will not be redirected to a file or piped to a shell command.
## Limitations of Redirection
Some limitations apply to redirection and piping within `cmd2` applications:
- Can only pipe to shell commands, not other `cmd2` application commands
- **stdout** gets redirected/piped, **stderr** does not
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