chore: bootstrap lean sysadmin-chronicles repo

Import the runnable game code, content, docs, scripts, and repo guidance while leaving local agent state, dependency installs, build output, and backup copies out of the published tree.
2026-05-02 11:49:07 -04:00
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+{
+  "id": "file-permissions",
+  "title": "File Ownership & Permissions",
+  "category": "sysadmin",
+  "tags": ["chown", "chmod", "permissions", "ownership", "ls"],
+  "updated": "2025-10-07",
+  "summary": "Understanding and fixing file ownership and permission bits.",
+  "sections": [
+    {
+      "heading": "Reading the Permission String",
+      "body": "<p>Run <code>ls -l</code> to see permissions. The first column looks like <code>-rwxr-xr--</code>.</p><ul><li>First character: <code>-</code> file, <code>d</code> directory, <code>l</code> symlink</li><li>Next three: owner read/write/execute</li><li>Next three: group read/write/execute</li><li>Last three: others read/write/execute</li></ul><p><code>r</code>=4, <code>w</code>=2, <code>x</code>=1. Add them up for octal notation: <code>rwx</code>=7, <code>rw-</code>=6, <code>r--</code>=4.</p>"
+    },
+    {
+      "heading": "chown — Changing Ownership",
+      "body": "<p>Change the owner and/or group of a file or directory.</p>",
+      "code": "chown user file               # change owner only\nchown user:group file         # change owner and group\nchown :group file             # change group only\n\n# Recursive — change everything under a directory\nchown -R user:group /path/to/dir"
+    },
+    {
+      "heading": "chmod — Changing Permissions",
+      "body": "",
+      "code": "chmod 644 file.txt            # rw-r--r-- (typical for files)\nchmod 755 /usr/local/bin/app  # rwxr-xr-x (typical for executables)\nchmod 700 ~/.ssh              # rwx------ (private directory)\nchmod 600 ~/.ssh/authorized_keys  # rw------- (private file)\n\n# Recursive\nchmod -R 755 /var/www/html\n\n# Symbolic form (add execute for owner only)\nchmod u+x script.sh"
+    },
+    {
+      "heading": "Common Patterns",
+      "body": "<table><tr><th>Mode</th><th>Numeric</th><th>Typical use</th></tr><tr><td><code>rw-r--r--</code></td><td>644</td><td>Regular files, config files</td></tr><tr><td><code>rwxr-xr-x</code></td><td>755</td><td>Directories, executables</td></tr><tr><td><code>rwx------</code></td><td>700</td><td>Private directories (e.g. ~/.ssh)</td></tr><tr><td><code>rw-------</code></td><td>600</td><td>Private files (e.g. private keys, authorized_keys)</td></tr><tr><td><code>rwxrwxr-x</code></td><td>775</td><td>Shared directories where the group needs write access</td></tr></table>"
+    },
+    {
+      "heading": "Checking Who Owns What",
+      "body": "",
+      "code": "ls -la /var/www/html          # list with ownership\nstat file.txt                 # detailed file metadata\nfind /path -user root         # find files owned by root\nfind /path -not -user deploy  # find files NOT owned by deploy"
+    },
+    {
+      "heading": "A Note on Recursive chown",
+      "body": "<p>When you run <code>chown -R</code>, it changes <em>everything</em> under the path—including files and subdirectories that may have intentionally different ownership. Know what you are targeting before running it on a live system. Check with <code>ls -laR</code> or <code>find</code> first.</p>"
+    }
+  ]
+}