# Running System Service Programs in the Terminal
**URL:** https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93
**Category:** Help / Tech Support
**Created:** [October 7, 2024, 9:05am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93 "2024-10-07T09:05:32Z")
**Posts on this page:** 14
**Page:** 1
### Author:  [@hamed](https://genode.discourse.group/u/hamed)
#### Post date: [October 7, 2024, 9:05am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/1 "2024-10-07T09:05:32Z")
I tried adding new commands to the provided terminal, and it was successful in cases where there were no system dependencies. However, the issue I’m facing is how to use programs that rely on system services, like `ping` or similar.
Is there any sample code or example available for this?
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### Author:  [@ttcoder](https://genode.discourse.group/u/ttcoder)
#### Post date: [October 9, 2024, 11:01am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/2 "2024-10-09T11:01:14Z")
I, too, tend to look for blue-prints and examples as a source of inspiration for such changes.
Genodians articles such as [this one](https://genodians.org/jschlatow/2024-06-04-goa-sculpt-vnc) tend to help in my case, for hand-crafted XML configuration. Or [this](https://github.com/genodelabs/genode/commit/f1c68e3be9424e280dee4b95f53f464a05200805) if you’re generating the XML from C++. I also keep tabs on how to configure Sculpt OS recipes and runtimes, as that can also be easily extrapolated to ‘raw’ XML configurations: [one](https://github.com/genodelabs/genode/commit/4044385fd5d136e139605f66fe59dc8af80ebcb2), [two](https://github.com/genodelabs/genode/commit/aeb42b0983143e6fe0a01f7f5316612709da1a9d)
YMMV (your mileage may vary) ^^
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### Author:  [@hamed](https://genode.discourse.group/u/hamed)
#### Post date: [October 9, 2024, 12:11pm UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/3 "2024-10-09T12:11:12Z")
I have added two types of programs to the terminal:
**First Program:**
```c
int main(int argc, char *argv[])
{
printf("------------ %s", argc <= 1 ? argv[0] : argv[2]);
}
```
**Second Program:**
```cpp
void Libc::Component::construct(Libc::Env &env)
{
Libc::with_libc([&] {
Genode::log("------------", &env);
env.parent().exit(0);
});
}
```
Both programs were placed in the `bin` folder and added to the terminal using the `tar` command provided in the XML structure. The first program produced the expected output. However, the second program encounters the following error:
```auto
[init -> /bin/bash -> 1] Error: LD: Non-RW/RX segment
[init -> /bin/bash -> 1] Error: Uncaught exception of type 'Linker::Invalid_file'
[init -> /bin/bash -> 1] Warning: abort called - thread: ep
```
The second code is a simple example to enable me to utilize all available tools in Genode.
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### Author:  [@cproc](https://genode.discourse.group/u/cproc)
#### Post date: [October 10, 2024, 10:29am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/4 "2024-10-10T10:29:05Z")
The `fork` / `execve` mechanism used by `bash` can currently only start POSIX programs.
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### Author:  [@ttcoder](https://genode.discourse.group/u/ttcoder)
#### Post date: [October 10, 2024, 10:35am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/5 "2024-10-10T10:35:57Z")
Makes sense – also a couple observations for hamed:
- you can use Genode features even in the version with main()
- the version with main() is the one where you need to call `with_libc()`, not the other one 😉 and even then, not in all cases, I think it’s only when mixing and matching POSIX code and Genode code (signal handlers etc) in the same thread – there’s still a lot I need to understand about `with_libc()` so do dig in that direction
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### Author:  [@hamed](https://genode.discourse.group/u/hamed)
#### Post date: [October 10, 2024, 12:20pm UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/6 "2024-10-10T12:20:05Z")
> [@cproc](#):
>
> The `fork` / `execve` mechanism used by `bash` can currently only start POSIX programs.
Is there really no way? Is there no possibility of using RPC either? If RPC can be used, please guide me.
For example, I would like to be able to run the ping program in a non-POSIX environment and receive its results using RPC, then display the output.
---
### Author:  [@ttcoder](https://genode.discourse.group/u/ttcoder)
#### Post date: [October 11, 2024, 9:12am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/7 "2024-10-11T09:12:25Z")
Seems to me if you really, really need your program to be launched from a command-line terminal or a bash script, then you’ll have to modify your program to have a main() function (which as noted, does not limit you in any way, it can still use Genode RPC and anything Genode has to offer: that’s how ports are made, like Falkon: Falkon is a posix app that uses the Qt library, which itself uses many Genode APIs).
Even so, you might still want to also look into `init`, since that’s the _native_ way of launching programs in Genode. (or to be more accurate, it’s a nice and convenient xml-piloted wrapper component on top of the Genode “child” API).
As to the native ping utility,
IIRC it outputs its results with Genode::log(), i.e. textual output to the LOG service. But its _return code_ might be usable from the outside though, didn’t check.
---
### Author:  [@cproc](https://genode.discourse.group/u/cproc)
#### Post date: [October 11, 2024, 9:23am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/8 "2024-10-11T09:23:36Z")
The preferred way for POSIX programs to interact with non-POSIX components is via VFS plugins. For example, you could have a POSIX `ping` wrapper program or shell script which writes an XML `init` configuration for the non-POSIX `ping` component to a file which is read as ROM by an `init` component which then starts the `ping` component. The log output of the `ping` component could then be redirected to a named pipe file which is read by the `ping` wrapper POSIX program using the `pipe` VFS plugin. Just an untested idea.
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### Author:  [@cproc](https://genode.discourse.group/u/cproc)
#### Post date: [October 11, 2024, 10:11am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/9 "2024-10-11T10:11:48Z")
> [@ttcoder](#):
>
> Seems to me if you really, really need your program to be launched from a command-line terminal or a bash script, then you’ll have to modify your program to have a main() function (which as noted, does not limit you in any way, it can still use Genode RPC and anything Genode has to offer: that’s how ports are made, like Falkon: Falkon is a posix app that uses the Qt library, which itself uses many Genode APIs).
Qt mainly uses VFS plugins like `lwip` or `lxip` for the network connection, or the `oss` VFS plugin for audio, but it also interacts with the `Gui` session directly. A problem with direct session use in POSIX programs is how to obtain the `Genode::Env` object which is needed for that. Qt applications use a special variant of the `posix` library named `qt5_component`, which passes this object to Qt before calling the `main()` function. The `fork` / `execve` mechanism assumes that `posix.lib.so` is used, so I think it would not be possible to start Qt applications directly from bash either.
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### Author:  [@ttcoder](https://genode.discourse.group/u/ttcoder)
#### Post date: [October 11, 2024, 10:40am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/10 "2024-10-11T10:40:04Z")
> [@cproc](#):
>
> The `fork` / `execve` mechanism assumes that `posix.lib.so` is used, so I think it would not be possible to start Qt applications directly from bash either.
Interesting, didn’t know that! That would likely also apply in my h/o/g library’s case: I don’t use `posix.lib.so` but re-implement its functionality in `haiku.lib.so` (to register `Env` etc), so apps that link against it would not be launchable from a bash terminal then. Never noticed that before because until now I’ve been launching apps only from the GUI (Deskbar).
Might be something to keep on my ‘radar’ in the long term, nothing urgent though.
---
### Author:  [@hamed](https://genode.discourse.group/u/hamed)
#### Post date: [October 12, 2024, 7:01am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/11 "2024-10-12T07:01:49Z")
Thanks! This is exactly the idea that came to my mind too. It seems like this is the only solution, and it works well for a program like `ping`. But in situations where performance is important, this approach might run into some challenges.
I’ll probably try to write a suitable wrapper, similar to `qt5_component`, that can retrieve the `env` variable and add RPC to the setup as well. I also hope to leverage the experiences of others from different branches.
Thanks again for your explanation. It confirmed that I’ve understood the key concepts of the Genode framework quite well, which I’m really glad about.
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### Author:  [@chelmuth](https://genode.discourse.group/u/chelmuth)
#### Post date: [October 12, 2024, 9:50am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/12 "2024-10-12T09:50:13Z")
May I ask, why you are sticking to the UNIX shell? All other components of Sculpt OS are managed by native Genode services.
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### Author:  [@hamed](https://genode.discourse.group/u/hamed)
#### Post date: [October 12, 2024, 10:31am UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/13 "2024-10-12T10:31:44Z")
I have reviewed Sculpt OS, and one of the serious shortcomings I noticed is the inability to easily add common system applications, such as network tools, to the OS. One major advantage of the Genode framework, however, is the ability to test and run a Linux kernel, which greatly simplifies development. I believe that if the framework supported common cross-platform applications, it would attract a significant number of developers. This would, in turn, transform it from being a specialized or educational OS into a mainstream operating system for embedded systems.
To that end, I first tried to familiarize myself with the concepts of the Genode framework. Adding a kiosk application to the system and working with dynamic configurations helped clarify these concepts to a good extent. However, I believe there are still some areas that need further discussion, which I plan to address in separate topics.
To deepen my understanding of Genode’s modular structure, I attempted to integrate POSIX-like programs into the UNIX shell. This was done to explore how a fully POSIX-compliant structure interacts with the Genode framework.
---
### Author:  [@chelmuth](https://genode.discourse.group/u/chelmuth)
#### Post date: [October 12, 2024, 1:16pm UTC](https://genode.discourse.group/t/running-system-service-programs-in-the-terminal/93/14 "2024-10-12T13:16:37Z")
Thanks for the clarification.
From my experience, the mentioned network tools (nmap, hping3, tshark, etc.) heavily depend on operating-system interfaces for some kind of _raw socket_ to craft special network packets and monitor all traffic. In addition other OS-specific features like /proc, /sys, or netlink sockets may be used to discover/adjust network configurations. Therefore, the success of _porting standard tools_ rises and falls with the implementation of these non-standard interfaces in our POSIX runtime (best as VFS plugins like @cproc metioned).