If the build closure contains some CA derivations, then we can't know
ahead-of-time that we won't build anything as early-cutoff might come-in
at a laster stage
gnu-config standardized on aarch64 for machine name so host_cpu part
of $system will always be aarch64. That means system will be
aarch64-darwin too.
uname however could report either “aarch64” (if gnu coreutils) or
“arm64” (if apple’s uname). We should support both for compatiblity
here.
As we are working towards Nix 3.0 we want to make sure that we make a
huge step forward in Nix's user experience. And once 3.0 is out of the
door we need to make sure that all future commands and features keep up
the standard of user experience.
This PR adds a CLI guideline document to the Nix documentation. Consider
this document a good starting point and a checklist when somebody will
be (re)implementing commands.
Clearly this guideline does nothing to improve user experience on its
own and can only be useful as long as it is going to be read and
cared for. But it is a first step into that direction.
using fallocate() to preallocate files space does more harm than good:
- breaks compression on btrfs
- has been called "not the right thing to do" by xfs developers
(because delayed allocation that most filesystems implement leads to smarter
allocation than what the filesystem needs to do if we upfront fallocate files)
Since c4c3c15c19 (#4251) building Nix for
macOS with sandboxing fails:
```
getting status of /nix/var/nix/profiles/per-user/root/channels/nixpkgs: Operation not permitted
```
This happens, because `EvalSettings::getDefaultNixPath` tries to access
paths outside the sandbox. Since the state-dir is not required for
doc generation, it is set to the dummy folder. This needs to be done
for all nix invocations during doc generation, as
`EvalSettings::getDefaultNixPath` is called unconditionally.
Without setting HGPLAIN, the user's environment leaks into
hg invocations, which means that the output may not be in the
expected format.
HGPLAIN is the Mercurial-recommended solution for this in that
it's intended for uses by scripts and programs which are looking
to parse Mercurial's output in a consistent manner.
