Update ssl-cert-file docs (#671)

README.md

@@ -424,7 +424,7 @@ Differing from the upstream [Nix](https://github.com/NixOS/nix) installer script
   * `extra-nix-path` is set to `nixpkgs=flake:nixpkgs`
 * an installation receipt (for uninstalling) is stored at `/nix/receipt.json` as well as a copy of the install binary at `/nix/nix-installer`
 * `nix-channel --update` is not run, `~/.nix-channels` is not provisioned
-* `NIX_SSL_CERT_FILE` is set in the various shell profiles if the `ssl-cert-file` argument is used.
+* `ssl-cert-file` is set in `/etc/nix/nix.conf` if the `ssl-cert-file` argument is used.
 
 ## Motivations
 
@@ -476,4 +476,4 @@ You can read the full privacy policy for [Determinate Systems][detsys], the crea
 [privacy]: https://determinate.systems/privacy
 [systemd]: https://systemd.io
 [wslg]: https://github.com/microsoft/wslg
-[nixgl]: https://github.com/guibou/nixGL
+[nixgl]: https://github.com/guibou/nixGL

src/settings.rs

@@ -183,7 +183,7 @@ pub struct CommonSettings {
     #[cfg_attr(feature = "cli", clap(long, env = "NIX_INSTALLER_PROXY"))]
     pub proxy: Option<Url>,
 
-    /// An SSL cert to use (if any), used for fetching Nix and sets `NIX_SSL_CERT_FILE` for Nix
+    /// An SSL cert to use (if any), used for fetching Nix and sets `ssl-cert-file` in `/etc/nix/nix.conf`
     #[cfg_attr(feature = "cli", clap(long, env = "NIX_INSTALLER_SSL_CERT_FILE"))]
     pub ssl_cert_file: Option<PathBuf>,