Libguestfs - Sep 2023 - [EXTERNAL] - Re: LIBGUESTFS mount disk failure

Thank you, Richard!

Guestfs_launch was failing due to internal program issue. Since guesfs_launch
creates new process for guesfs process.

Hence, Guestfs_launch was failing since new process creation failed in internal
program due to remote connection.


We resolved using Deamon and Sender logic. 
When Deamon will receive message from sender to launch guest it will launch
guestfs runner program => Happy Path is working.

One more help is needed : https://github.com/libguestfs/libguestfs/issues/124
/***************************************/
I can get guestfs_last_error using function_callback and write to log file.
But "event Handling" is not working Also, std::cout and std::cerr
still printing on terminal.

Is there any workaround for Event Handling?
 How to completely disable/enable standard output?
/***********************************/

In short, Any Debugging sample program,
https://github.com/libguestfs/libguestfs/issues/124

Libguestfs:issue$124, contains sample program.


Thanks
RR

-----Original Message-----
From: Richard W.M. Jones <rjones at redhat.com> 
Sent: Sunday, September 17, 2023 2:12 PM
To: Raja Ram Sharma <rsharma6 at opentext.com>
Cc: Teja Konapalli <tkonapalli at opentext.com>; libguestfs at redhat.com;
Divyanshu Kumar <dkumar3 at opentext.com>
Subject: Re: [EXTERNAL] - Re: LIBGUESTFS mount disk failure

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On Sun, Sep 17, 2023 at 03:55:24AM +0000, Raja Ram Sharma
wrote:
> Hi Richard,
>
> Wish you a happy weekend!
>
> Guestfs_launch fails after below error :
>       ^^^^
>       libguestfs: is_openable: /dev/kvm: No such file or directory
>       libguestfs: trace: get_backend_setting "force_tcg"
>       libguestfs: trace: get_backend_setting = NULL (error)
>       ^^^
> Same line has also printed in " LIBGUESTFS_BACKEND=direct
libguestfs-test-tool " at line $96-$98
>       ^^^
>       Could not access KVM kernel module: No such file or directory
>       qemu-kvm: failed to initialize KVM: No such file or directory
>       ^^^
Thanks for providing the second output.

The above messages aren't errors.

I really need much more context.  I need to see the program that you're
trying to run, or a self-contained reproducer, and I also need to see the
_complete_ output from the program from start to finish, not just small parts of
it.

Rich.

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On Sun, Sep 17, 2023 at 04:11:25PM +0000, Raja Ram Sharma
wrote:
> One more help is needed :
https://github.com/libguestfs/libguestfs/issues/124
> /***************************************/
> I can get guestfs_last_error using function_callback and write to log file.
> But "event Handling" is not working Also, std::cout and std::cerr
still printing on terminal.
> Is there any workaround for Event Handling?
>  How to completely disable/enable standard output?
> /***********************************/
> 
> In short, Any Debugging sample program,
https://github.com/libguestfs/libguestfs/issues/124
In the two programs in that issue, the first program sets an event
callback and the second program sets an error handler.  To capture all
messages you must set both together.

If you can produce a single, short reproducer which uses both types of
handlers and still prints to stderr, then I can look at that.

Rich.

-- 
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Read my programming and virtualization blog: http://rwmj.wordpress.com
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