Map --help flag to "man <command>" for more NixOS commands

nixos/modules/installer/tools/nixos-build-vms/nixos-build-vms.sh

@@ -2,14 +2,9 @@
 
 # Shows the usage of this command to the user
 
-showUsage()
-{
-    echo "Usage: $0 network_expr"
-    echo "Options:"
-    echo
-    echo "--no-out-link   Do not create a 'result' symlink"
-    echo "--show-trace    Shows the output trace"
-    echo "-h,--help       Shows the usage of this command"
+showUsage() {
+    exec man nixos-build-vms
+    exit 1
 }
 
 # Parse valid argument options

nixos/modules/installer/tools/nixos-install.sh

@@ -19,6 +19,10 @@ while [ "$#" -gt 0 ]; do
             absolute_path=$(readlink -m $given_path)
             extraBuildFlags+=("$i" "/mnt$absolute_path")
             ;;
+        --help)
+            exec man nixos-install
+            exit 1
+            ;;
         *)
             echo "$0: unknown option \`$i'"
             exit 1

nixos/modules/installer/tools/nixos-option.sh

@@ -8,36 +8,8 @@
 export NIXOS_CONFIG
 
 usage () {
-  echo 1>&2 "
-Usage: $0 [-v] [-d] [-l] [--xml] OPTION_NAME
-       $0 --install
-
-This program allows you to inspect the current value of NixOS
-configuration options.  It can also generate a basic NixOS
-configuration file.
-
-Options:
-
-  -i | --install        Write a template NixOS configuration file to
-                        ${mountPoint:+$mountPoint/}$NIXOS_CONFIG.
-  -v | --value          Display the current value, based on your
-                        configuration.
-  -d | --description    Display the default value, the example and the
-                        description.
-  -l | --lookup         Display where the option is defined and where it
-                        is declared.
-  --xml                 Print an XML representation of the result.
-                        Implies -vdl options.
-  --help                Show this message.
-
-Environment variables affecting $0:
-
-  \$mountPoint          Path to the target file system.
-  \$NIXOS_CONFIG        Path to your configuration file.
-
-"
-
-  exit 1;
+    exec man nixos-rebuild
+    exit 1
 }
 
 #####################