Add Exclude Certain Files From An rsync Run as a unix til

unix/exclude-certain-files-from-an-rsync-run.md

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+# Exclude Certain Files From An rsync Run
+
+The `rsync` command can be used to copy files from one directory to another (as
+well as to or from a remote system). It is generally used to broadly
+synchronize all files in the source directory to a destination directory.
+
+I recently ran into a situation where I wanted to recursively (`-a`) sync files
+from a cloned git repository. I didn't want quite everything—namely dotfiles,
+dot-directories (such as `.git/`), and top-level markdown files.
+
+This is where the `--exclude` flag comes in to play.
+
+The dotfiles and dot-directories can be excluded with the `.*` pattern.
+
+```bash
+$ rsync -anv --exclude='.*' dir1/ dir2
+```
+
+The top-level markdown files can be excluded, without excluding nested markdown
+files, with the `./*.md` pattern.
+
+```bash
+$ rsync -anv --exclude='.*' --exclude='./.*md' dir1/ dir2
+```
+
+The `-n` and `-v` flags together provide a dry run of this with results that I
+can check. Once I'm ready to do the real thing, I can remove those.
+
+```bash
+$ rsync -a --exclude='.*' --exclude='./.*md' dir1/ dir2
+```
+
+See `man rsync` for more details.