# output (create output source for event forwarding) ### Command > output ### Syntax > output > > output \[create Name (string)] \[file|namedpipe|tcp|module Address (string)] > > output \[open|close Name (string)] ### Description Create, open, or close a source output for event forwarding. You can read more about **event forwarding** [here](https://docs.hyperdbg.org/tips-and-tricks/misc/event-forwarding). Examples of using this mechanism in different programming languages are available here: {% embed url="" %} ### Parameters **\[create Name (string)]** The name of the instance output to be created. **\[file|namedpipe|tcp|module Address (string)]** Type and address of the target resource. **\[open|close Name (string)]** The action of this command or whether this command tries to open an output source or close it combined with its name. {% hint style="success" %} If you don't specify any parameters to the '**output**' command, it shows a list of output sources and their status. {% endhint %} ### Examples The following command creates an output source, which is a `file` and the results of the command (script) will be saved into the `c:\users\sina\desktop\output.txt`. ```diff HyperDbg> output create MyOutputName1 file c:\users\sina\desktop\output.txt ``` The following command creates an output source, which is a `tcp` and the results of the command (script) will be sent into the `192.168.1.10:8080`. ```diff HyperDbg> output create MyOutputName2 tcp 192.168.1.10:8080 ``` The following command creates an output source, which is a `namedpipe` and the results of the command (script) will be sent into the `\\.\Pipe\HyperDbgOutput`. ```diff HyperDbg> output create MyOutputName3 namedpipe \\.\Pipe\HyperDbgOutput ``` You cannot use the above resources until you **open** them using the following command. This command opens an output source (named "**MyOutputName1**") that was previously created by the output's **create** parameter. ```diff HyperDbg> output open MyOutputName1 ``` When you finished using an output source, you can **close** it using the following command. Once you close an output source, you cannot use it anymore, and also, you **CANNOT** open it again, but once again, you can **create** a new source with the same address but with a different **name**. ```diff HyperDbg> output close MyOutputName1 ``` After creating and opening the output source, you can use its name in all HyperDbg events. You should pass `output {MyOutputName1}` when you are creating an event, for example [!syscall](https://docs.hyperdbg.org/commands/extension-commands/syscall) is an event so that you can use it like this : ```diff HyperDbg> !syscall script { print(@rax); } output {MyOutputName1} ``` It is also possible to send the results to several output sources. You should separate the output names with `,` . For example : ```diff HyperDbg> !syscall script { print(@rax); } output {MyOutputName1 , MyOutputName2 , MyOutputName3} ``` You can specify up to `5` output sources in the default build of HyperDbg, but if you need more output sources for a single event, then you should compile HyperDbg with different configurations as described on [Customize Build](https://docs.hyperdbg.org/tips-and-tricks/misc/customize-build) and change the `DebuggerOutputSourceMaximumRemoteSourceForSingleEvent`. Starting from v0.10, HyperDbg supports modules (DLLs) as functions directly load DLLs and have the ability to forward events to functions. Note that, DLLs should be compiled into 64-bit binaries (32-bit binaries are not supported). Examples of DLLs are available in [Rust](https://github.com/HyperDbg/event-forwarding-examples/tree/main/Rust/module) and [C++](https://github.com/HyperDbg/event-forwarding-examples/tree/main/C%2B%2B/module). Generally, DLLs (in all low-level languages) should export a function with the name `hyperdbg_event_forwarding` with the first parameter as a pointer to the buffer message and the second parameter as an integer with the size that will be called by HyperDbg's event forwarding module once an event is triggered. The following example is the definition of the function in C/C++ (You can do the same in Rust, GO, etc.). ```cpp hyperdbg_event_forwarding(const char* buffer_message, unsigned int buffer_length); ``` After compiling the above function and exporting the above function (e.g., by using `__declspec(dllexport)`), you can open a `module` using the following command: ``` output create MyOutputName1 module C:\module\event_forwarding_module.dll ``` and after that, open it using the following command: ``` output open MyOutputName1 ``` and then (same as above examples) you can pass the events using the following event: ```c !epthook nt!ExAllocatePoolWithTag script { printf("Pool allocation called!"); } output { MyOutputName1 } ``` In case, you want to see a list of sources, you can use the '**output**' command without any parameter. ``` HyperDbg> output 1 file not opened MyOutputName1 2 file opened MyOutputName2 3 file not opened MyOutputName3 ``` ### IOCTL None ### Remarks You can use this command to forward the scripts' results from all the [events](https://docs.hyperdbg.org/design/debugger-internals/events). {% hint style="danger" %} You **cannot** use event forwarding in the immediate messaging mode in events (`imm no`). {% endhint %} ### Requirements None ### Related [Event Forwarding](https://docs.hyperdbg.org/tips-and-tricks/misc/event-forwarding)