Building and TestingYou can now try to build Hello. Of course, you could do
-nix-env -f pkgs/top-level/all-packages.nix -i hello,
-but you may not want to install a possibly broken package just yet.
-The best way to test the package is by using the command nix-build, which builds a Nix
-expression and creates a symlink named result in
-the current directory:
+nix-env -i hello, but you may not want to install a
+possibly broken package just yet. The best way to test the package is by
+using the command nix-build,
+which builds a Nix expression and creates a symlink named
+result in the current directory:
-$ nix-build pkgs/top-level/all-packages.nix -A hello
+$ nix-build -A hello
building path `/nix/store/632d2b22514d...-hello-2.1.1'
hello-2.1.1/
hello-2.1.1/intl/
@@ -29,8 +28,7 @@ $ ./result/bin/hello
Hello, world!
The option selects
-the hello attribute from
-all-packages.nix. This is faster than using the
+the hello attribute. This is faster than using the
symbolic package name specified by the name
attribute (which also happens to be hello) and is
unambiguous (there can be multiple packages with the symbolic name
@@ -69,7 +67,7 @@ block (or perform other derivations if available) until the build
finishes:
-$ nix-build pkgs/top-level/all-packages.nix -A hello
+$ nix-build -A hello
waiting for lock on `/nix/store/0h5b7hp8d4hqfrw8igvx97x1xawrjnac-hello-2.1.1x'
So it is always safe to run multiple instances of Nix in parallel