How do I ignore hidden files in Linux

Question

When working with Linux commands like ls, find, and rsync, I often want to ignore hidden files (.*). My questions are:

• What command-line options prevent hidden files from being listed?
• How to ensure scripts or backup tools exclude hidden files.
• How to handle cases where I need to selectively include/exclude specific dotfiles.
  Examples using bash, rsync, or find would be helpful.

Answer 1

In Linux, hidden files and directories are those whose names begin with a dot (.). By default, commands like ls, find, and rsync include these hidden files in their operations. However, there are scenarios where you might want to exclude hidden files from your command outputs or operations. Below are methods to achieve this for each command, along with examples and use cases.

1. Preventing Hidden Files from Being Listed

• Using ls Command:

  The ls command lists directory contents. To exclude hidden files (those starting with a dot), you can use:

ls -l | grep -v '^\.'

Explanation:

• ls -l: Lists files in long format.
• `grep -v '^.': Filters out entries that start with a dot.

Use Case: When you want to view all non-hidden files in a directory.

• Using find Command:

  The find command searches for files in a directory hierarchy. To exclude hidden files and directories:

find . -name '[!.]*'

Explanation:

• .: Starts the search from the current directory.
• -name '[!.]*': Matches files that do not start with a dot.

Use Case: When searching for files but wanting to exclude hidden ones.

2. Ensuring Scripts or Backup Tools Exclude Hidden Files

• Using rsync Command:

  rsync is commonly used for backups and file synchronization. To exclude hidden files during synchronization:

  rsync -av --exclude='.*' source/ destination/ 

Explanation:

• -av: Archive mode and verbose output.
• --exclude='.*': Excludes files and directories starting with a dot.

Use Case: When backing up a directory but omitting hidden files and directories.

• In Shell Scripts:

  When writing shell scripts that process files, you can exclude hidden files using a loop:

  for file in *; do
      if [ -f "$file" ]; then
          # Process $file
      fi
  done

Explanation:

• *: Matches all non-hidden files.
• [ -f "$file" ]: Checks if it's a regular file.

Use Case: Processing all visible files in a directory while ignoring hidden ones.

3. Selectively Including/Excluding Specific Dotfiles

• Using rsync with Include and Exclude Options:

  To include specific hidden files while excluding others:

rsync -av --include='.bashrc' --exclude='.*' source/ destination/

Explanation:

• --include='.bashrc': Includes the .bashrc file.
• --exclude='.*': Excludes all other hidden files.

Use Case: Backing up a directory while including only specific configuration files.

• Using find to Exclude Specific Dotfiles:

  To find all files except a specific hidden file:

find . -not -name '.git' -not -path '*/\.*'

Explanation:

• -not -name '.git': Excludes the .git directory.
• -not -path '*/\.*': Excludes all hidden files and directories.

Use Case: Searching for files while excluding version control directories and other hidden files.

Additional Considerations:

• Globbing Patterns:

  In shell commands, patterns like * match all non-hidden files. To include hidden files, you can use .* (for hidden files) along with *:

echo * .*

Note: Be cautious with .* as it matches . (current directory) and .. (parent directory) as well.

• Using shopt in Bash:

  Bash provides the shopt builtin to control shell options. To include hidden files in pathname expansion:

shopt -s dotglob

• dotglob: When set, glob patterns match hidden files.

Use Case: When you want wildcard patterns to include hidden files in script operations.

By utilizing these commands and options, you can effectively manage the inclusion or exclusion of hidden files in your Linux workflows.