GitHub's website will delete a file, but only one at a time, and every delete is its own commit. My site deploys from GitHub, so each of those commits would also start a new deploy. Thirty files, thirty deploys. No thanks.

Press the period key

On any repo page on github.com, press . (the period key). GitHub opens the repo in a full VS Code editor right in the browser, at github.dev. There's nothing to install. Changing github.com to github.dev in the address bar does the same thing, and so does going to vscode.dev/github/you/yourrepo.

Delete in bulk

1. In the Explorer on the left, open the folder you're cleaning up.
2. Ctrl+click each file or folder you want gone (Cmd+click on a Mac). Shift+click selects a whole range.
3. Right-click any of the selected items and choose Delete. Confirm if it asks.

Nothing has changed on GitHub yet. The deletes only exist in the editor until you commit.

Commit once

1. Click the Source Control icon, the third one down on the far left. It shows a count of your changes.
2. Check the list. Every file you deleted shows up crossed out, with a D next to it.
3. Type a message, such as "Remove old backups", and click Commit & Push.

That's one commit, and one deploy.

Bonus: move a file up a folder

I also had one file I wanted to keep in the repo but off the website, so it needed to move up two folders. On the regular github.com site, open the file and click the pencil to edit it. Click at the very start of the filename box and type ../ once for each folder you want to move up. I pressed Backspace there instead, which pulls the folder names back into the box so you can delete them. Either way, the folder path shown next to the box tells you where the file will land. Then commit.

Fair warning

There's no undo button, and the commit goes straight to your live branch. Check the Source Control list before you push. If you do delete the wrong thing, Git still has it. Open the repo's commit history, find the file in the commit before the delete, and add it back.

At any rate, it beat thirty rounds of clicking Delete file.

Everything below runs in PowerShell. I tried Cygwin first, and it didn't go well (more on that at the end).

1. Make the key

PS> ssh-keygen -t ed25519 -C "you@example.com"

Press Enter to keep the default location, C:\Users\you\.ssh\id_ed25519. Then press Enter twice for no passphrase, or type one. If you set one, Git asks for it every time you push.

2. Copy the public key, not the fingerprint

When ssh-keygen finishes, it prints a line that starts with SHA256: and ends with your email. That's the key's fingerprint, not the key. I pasted it into GitHub anyway and got this.

Key is invalid. You must supply a key in OpenSSH public key format

The key itself lives in the .pub file. This copies it to the clipboard.

PS> Get-Content $HOME\.ssh\id_ed25519.pub | Set-Clipboard

It's one long line that starts with ssh-ed25519 AAAAC3NzaC1lZDI1NTE5 and ends with your email. Never copy the file without .pub. That one is your private key, and it stays on your machine.

3. Add it to your account, not your repo

The SSH keys page lives in your account settings, not in any repo. The quickest way there is to go straight to github.com/settings/keys while you're signed in. To click your way there, use your profile picture in the top-right corner of any GitHub page, then Settings, then SSH and GPG keys under Access in the left sidebar.

Click New SSH key, give it a title like "Laptop", leave Key type set to Authentication Key, paste the key into the Key box and click Add SSH key.

I first went looking under the repo's own Settings tab. That only has Deploy keys, which work for that one repo.

4. Test it

PS> ssh -T git@github.com
The authenticity of host 'github.com (140.82.112.3)' can't be established.
ED25519 key fingerprint is SHA256:+DiY3wvvV6TuJJhbpZisF/zLDA0zPMSvHdkr4UvCOqU.
Are you sure you want to continue connecting (yes/no/[fingerprint])? yes
Hi you! You've successfully authenticated, but GitHub does not provide shell access.

That fingerprint is the one GitHub publishes for its servers, so you know you reached the real GitHub. "No shell access" is normal.

5. Switch your repo from HTTPS to SSH

From inside the repo, this rewrites the remote's address in place, so you don't have to retype the repo name.

PS> git remote get-url origin
https://github.com/you/yourrepo.git
PS> git remote set-url origin ((git remote get-url origin) -replace '^https://github\.com/', 'git@github.com:')
PS> git remote get-url origin
git@github.com:you/yourrepo.git
PS> git fetch

If git fetch comes back without asking you to log in, you're done.

Why Cygwin ate my passphrase

I started out in Cygwin. It turned out both commands were the Windows versions, not Cygwin's.

$ which git ssh
/cygdrive/c/Program Files/Git/cmd/git
/cygdrive/c/WINDOWS/System32/OpenSSH/ssh

Windows programs and Cygwin's terminal window don't always agree on hidden typing. ssh-keygen asked for the passphrase twice, I typed the same thing both times, and it still said this.

Passphrases do not match.  Try again.

Run ssh-keygen from PowerShell and the problem goes away. Two more Cygwin gotchas: Cygwin's ~ isn't your Windows home folder, so the key is under /cygdrive/c/Users/you/.ssh/. And Cygwin has a handy clipboard device.

$ cat /cygdrive/c/Users/you/.ssh/id_ed25519.pub > /dev/clipboard

If the test just hangs

Some networks block port 22, the usual SSH port. GitHub also answers SSH on port 443, which is almost never blocked. Add this to C:\Users\you\.ssh\config and try again.

Host github.com
  Hostname ssh.github.com
  Port 443
  User git

One last thing that tripped me up afterward. git pull updates the whole repo wherever it lives. It doesn't drop files into whatever folder you happen to be standing in. I learned that one the slow way.

When mysysad.com came back as a toolkit, the old posts were gone. Any old link or bookmark just led to an error page, and that bugged me. So I rebuilt all 429 posts from my old Blogger export and put each one back at its original address. A link like this one works again, exactly as it did in 2008.

www.mysysad.com/2008/04/reset-user-account-password-example-for.html

What changed

• Only small fixes, so the posts display correctly. The rest is the way I wrote it back then.
• Every post has a note at the top about what has changed since. Most were written on Solaris, and a lot of it is history now.
• Every post also reminds you to check commands, options and file paths against your own system before using them on a live one.
• Most posts end with a link to the tool on this site that does the same job today.

Finding things

The Archive page lists every post by year and month. You can search titles and topics, or narrow the list to one topic, such as Solaris & Sun, Shell & text, or Networking & mail. Each year and month has its own page too, like 2008.

Fair warning: some of these are very much of their time. There are posts about Solaris zones, Sybase logins and the Vista On-Screen Keyboard. But a surprising number of the shell one-liners still work today, and that was the whole point of the blog.

Next up, new posts. It's been a while.