[Nix-dev] Patching uname in stdenv?

[Marco Maggesi]

[sorry for the previous incomplete message]

On Aug 17, 2011, at 12:47 PM, Lluís Batlle i Rossell wrote:

>> The point is that these scripts depend on the version of the running kernel.
>> Also they do work on Linux in general, not necessarily on NixOS, and they need to be re-run each time the kernel is updated.
> 
> How can it be? I assume you mean blcr built from nixpkgs.
> 
> BLCR should fail to work in kernels older to the kernelHeaders in nixpkgs. And
> the kernelHeaders in nixpkgs should be the only determinant of what kernels blcr
> can work on.

This is interesting.
I should consider your remark to improve my build scripts.
The truth is that I don't understand the implementation details of BLCR.
(And, to be honest, I try to keep myself away as much as possible from this kind of low-level details.)

I simply make the assumptions that:
1. BLCR is installed on the system (I don't care how this is done, e.g., it can be installed by hand on an ubuntu server) and
2. I want to run checkpointed binaries that matches both the kernel and the BLCR installation that has been used to produce them.

These assumption are probably too restrictive, but they have an advantage:
they give a simple model and they do not depend on how the checkpointing software works internally.
For instance I use the same technique with other checkpointing software like dmtcp.
(But perhaps your remark applies equally to dmtcp, I don't know.)

Marco