Hi Satish,
You can set environment variables within the context of the command that you
are executing as opposed to exporting them for the whole system. If you try
running nginx as per the wiki page mentioned previously, you should be able to
confirm LD_PRELOAD is not globally set after you
Hi Florin,
Thank you for clarifying. You said that when the LD_PRELOAD env variable
is set just before I start the application then only that application
syscalls are intercepted. Can you explain how is that mapping is done ( To
determine which application socket API needs to be intercepted)
?
Hi Satish,
If the LD_PRELOAD env variable is only set when starting the application, only
that application’s syscalls are intercepted. Also note that we don’t intercept
all syscalls (check ldp.c for more details). So yes, the architecture in your
diagram should be possible.
Regards,
Florin
Hi Satish,
You can find an example of how to use Nginx with LDP here [1]. In general you
can find host stack documentation here [2].
Regards,
Florin
[1] https://wiki.fd.io/view/VPP/HostStack/LDP/nginx
[2] https://wiki.fd.io/view/VPP/HostStack
> On Jul 22, 2021, at 7:27 AM, satish amara
Hi,
I see we have a couple of options for user applications to use the VPP
TCP/IP stack. Either by VCL or LD_PRELOAD. I am trying to understand if we
can selectively intercept syscalls and injects them into VLS for specific
applications. Is LD_PRELOAD can application specific. If so what is the
