[augeas-devel] Saving changed tree to file does not work but no error message

[Christoph Molitor]

Hello Raphaël,

thanks for your reply and your suggestions.
I added some code to read the error messages. 
When I execute the code there are no error messages but still the changes made to the value of one node are not saved back to the configuration file.
The latest source code can be found here:
https://github.com/cmolitor/AugeasDemoC/blob/simple/src/main.cpp

I also went through all the steps using augtool and added the commands as comments to the source code.
If I execute the commands in augtool the changes are saved to the configuration file.

In general, I can load the configuration file, change the value, check that the value has been really changed by reading it again. Calling aug_save() does not give an error message but still the changes are not saved to the file.

I tried this with augeas version 1.2 and 1.4.

It would be great if I could get further advice how to proceed or a hint what I am doing wrong.

I will also have a look at netcf but could not find a detailed documentation yet.

Thanks,
Christoph





Am 04.01.2016 um 09:44 schrieb Raphaël Pinson <raphael.pinson at camptocamp.com>:

> Hello Christoph and happy new year to you too!
> 
> 
> Your code doesn't check for errors (either parsing or saving errors). You could add checks (looking for `/augeas//error` nodes) just after your call to aug_load (for parsing errors) and to aug_save (for saving errors).
> 
> One way to debug your code would also be to try it with augtool, which would be easier to debug.
> 
> Also, are you aware of the netcf project, which provides a higher API on top of Augeas to access and modify /etc/network/interfaces?
> 
> 
> 
> Cheers,
> 
> Raphaël
> 
> 
> 
> 
> 
> On Fri, Jan 1, 2016 at 5:05 PM, Christoph Molitor <christoph.molitor at googlemail.com> wrote:
> Dear all,
> 
> first of all a happy new year to everyone.
> 
> I am trying to use the augeas C API to apply changes to the "/etc/network/interfaces" file.
> So far I was able to apply changes to the tree. However, I am not able to save the changes back to the file.
> First, I thought it is a problem with the permissions. However, I copied the interfaces file to a different folder and it still does not work.
> Using the command line tool augtool, I am able to make the changes and save them to the file.
> 
> I uploaded an (almost) minimal version of my program to:
> https://github.com/cmolitor/AugeasDemoC
> 
> The repository includes an example „interfaces“.
> I am working on a Raspberry Pi with Raspbian Jessie.
> It would be great if someone could give me a hint what I am doing work and where the problem might come from.
> 
> Thanks for your support!
> 
> Christoph
> 
> _______________________________________________
> augeas-devel mailing list
> augeas-devel at redhat.com
> https://www.redhat.com/mailman/listinfo/augeas-devel
> 
> 
> 
> -- 
> Raphaël Pinson
> Infrastructure Developer & Training Leader
> +33 458 482 013
> 
> Camptocamp France
> Savoie Technolac
> BP 352
> 48, avenue du Lac du Bourget
> 73372 Le Bourget du Lac, Cedex
> www.camptocamp.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/augeas-devel/attachments/20160110/1c1776a3/attachment.htm>