* Help text for all (non-script) programs, so no more:

$ nix-instantiate --help
error: unknown flag `--help`
Try `nix-instantiate --help' for more information.

:-)

1 files changed, 31 insertions, 0 deletions

diff --git a/src/nix-env/help.txt b/src/nix-env/help.txt
new file mode 100644
index 000000000..69c474294
--- /dev/null
+++ b/src/nix-env/help.txt
@@ -0,0 +1,31 @@
+nix-env [OPTIONS...] [ARGUMENTS...]
+
+`nix-env' is a tool to manipulate Nix user environments.
+
+Operations:
+
+  --install / -i FILE: add a derivation to the user environment
+  --uninstall / -u: remove a derivation to the user environment
+  --query / -q: perform a query on an environment or Nix expression
+
+The previous operations take a list of derivation names.  The special
+name `*' may be used to indicate all derivations.
+
+  --version: output version information
+  --help: display help
+
+Query types:
+
+  --name: print derivation names (default)
+  --expr / -e: print derivation store expression
+  --status / -s: print installed/present status
+
+Query sources:
+
+  --installed: use installed derivations (default)
+  --available / -f FILE: use derivations available in expression FILE
+
+Options:
+
+  --verbose / -v: verbose operation (may be repeated)
+  --keep-failed / -K: keep temporary directories of failed builds