cmd/cammount: add more documentation and examples to help people get started with PerkeepFs

Fixes #789

Change-Id: I9f0d0a8a823902ed2ae1bf83d4a5b58fadac1d7d

cmd/cammount/doc.go

@@ -15,16 +15,94 @@ limitations under the License.
 */
 
 /*
-The cammount tool mounts a root directory blob onto the given mountpoint. The blobref can be given directly or through a share blob URL. If no root blobref is given, an automatic root is created instead.
+The cammount tool mounts a root directory blob onto the given
+mountpoint. The blobref can be given directly or through a share blob
+URL. If no root blobref is given, an automatic root is created
+instead.
+
+Mounting
+
+Execute the following commands in a shell to mount a Perkeep directory in your home directory.
+
+  mkdir ~/Perkeep
+  cammount ~/Perkeep
+  cd ~/Perkeep
+  ls -C1
+
+  WELCOME.txt
+  at
+  date
+  recent
+  roots
+  sha1-xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+  tag
 
 
-Usage:
+Creating a Root Node
 
-	cammount [opts] <mountpoint> [<root-blobref>|<share URL>]
-	-debug=false: print debugging messages.
-	-server="": Camlistore server prefix.
-	If blank, the default from the "server" field of ~/.camlistore/config is used.
-	Acceptable forms: https://you.example.com, example.com:1345 (https assumed), or
-	http://you.example.com/alt-root
+Files and directories are anchored in a root node.  You can view and
+create Root nodes in the roots directory.  For example to create a
+Photos root node execute the following commands:
+
+  cd ~/Perkeep
+  mkdir roots/Photos
+  cd roots/Photos
+  cp -R ~/Photos/* .
+
+
+Accessing Recent Items
+
+A list of recently accessed items are visible in the recent directory.
+
+  cd ~/Perkeep/recent
+  ls -C1
+
+  IMG_20171104_193001.jpg
+  IMG_20171104_205408_thumbnail.jpg
+  IMG_20171208_070038.jpg
+  test.txt
+
+
+Accessing Content at a specific Point in Time
+
+The at directory contains full instructions in the README.txt file contained within.
+
+
+Accessing a specific Node
+
+You can directly access a specific directory by using the full sha1 identifier.
+
+   cd ~/Perkeep
+   cd sha1-xxx # where xxx is the full 16 character identifier
+
+
+Full Command Line Usage
+
+  cammount [opts] [<mountpoint> [<root-blobref>|<share URL>|<root-name>]]
+  -debug
+        print debugging messages.
+  -help
+        print usage
+  -legal
+        show licenses
+  -open
+        Open a GUI window
+  -secret-keyring string
+        GnuPG secret keyring file to use.
+  -server string
+        Perkeep server prefix.
+        If blank, the default from the "server" field of the default
+        config is used. Acceptable forms:
+           https://you.example.com,
+           example.com:1345 (https assumed), or
+           http://you.example.com/alt-root
+  -term
+        Open a terminal window. Doesn't shut down when exited. Mostly for demos.
+  -verbose
+        extra debug logging
+  -version
+        show version
+  -xterm
+        Run an xterm in the mounted directory. Shut down when xterm ends.
 */
 package main // import "camlistore.org/cmd/cammount"

pkg/fs/root.go

@@ -99,7 +99,7 @@ func (n *root) Lookup(ctx context.Context, name string) (fs.Node, error) {
 	case ".quitquitquit":
 		log.Fatalf("Shutting down due to root .quitquitquit lookup.")
 	case "WELCOME.txt":
-		return staticFileNode("Welcome to CamlistoreFS.\n\nFor now you can only cd into a sha1-xxxx directory, if you know the blobref of a directory or a file.\n"), nil
+		return staticFileNode("Welcome to PerkeepFS.\n\nMore information is available in the cammount documentation.\n\nSee https://perkeep.org/cmd/cammount/\n"), nil
 	case "recent":
 		return n.getRecentDir(), nil
 	case "tag", "date":