updated to fix some typos and give some superficial logic for how to …

…build acl lists

labguide/computing/sherlock/access-and-resources.md

@@ -67,10 +67,19 @@ A useful and more interacrtive version of this command is `ncdu`.
 To use `ncdu`, add the following line to the bottom of your `~/.bash_profile`, which will load the `ncdu` module each time you log in to Sherlock:
 
 ```bash
-$ ml system ncdu
+ml system ncdu
 ```
 
-In future login session, you can access the `ncdu` command via
+and then update your `~/.bash_profile` for the current session with:
+
+```bash
+$ source ~/.bash_profile
+```
+
+which will allow the current session to load the new module updated in your bash profile for `ncdu`.
+For future login sessions, re-sourcing your `~/.bash_profile` is unnecessary.
+
+In the present and future login sessions, you can access the `ncdu` command via:
 
 ```bash
 $ ncdu <folder>

labguide/computing/sherlock/data-management.md

@@ -18,7 +18,8 @@ Datasets that are temporary, or files generated for analyses that are not intend
 #### Restricting access
 
 Some data resources cannot be shared across the lab and instead need to be restricted to lab members with Data Usage Agreement (DUA) access.
-The following can be adapted to restrict ACLs (access control list) to only the appropriate subset of lab members:
+This can be done via access control lists (ACLs), which allow a resource to be owned by a particular owner/group, but applies an additional  more specific set of permissions.
+The following can be adapted to restrict ACLs to an appropriate subset of lab members:
 
 ```{.bash filename="protect_access.sh"}
 #!/bin/bash
@@ -36,11 +37,13 @@ fi
 
 read -p "Enter the username: " user_name
 
-# set restrictions
+# set restrictions, repeating once for each desired user
 echo -e "Setting restrictions for ${user_name} as rxw for folder: /n ${dir_name}"
 setfacl -R -m u:$user_name:rwx $dir_name
 setfacl -R -d -m u:$user_name:rwx $dir_name
+# repeat the above commands, replacing $user_name with the usernames
+# for additional members
 
 # rm default permissions for the group -- oak_russpold
 setfacl -m d::group:oak_russpold:--- $dir_name
-```
+```