Comparing Unix-Style Commands on Linux, macOS, and Windows

1. awk

Linux:

• Typical Version: GNU awk (gawk).

• Features: Extensive support for extensions (networking, internationalization, etc.) and numerous GNU-specific options.

• Example:

  awk '{ print $1 }' file.txt

macOS:

• Typical Version: Often uses the BSD variant or nawk (New AWK).

• Differences: Some GNU-specific extensions might be missing or behave differently.

• Example:

  awk '{ print $1 }' file.txt

  (Behavior is similar, but if you use GNU extensions you might need to install GNU awk via Homebrew.)

Windows:

• Availability: Not available by default.

• Options: Can be obtained through:

  • Cygwin/Git Bash/WSL: Install GNU awk.

  • GnuWin32: A native port.

• Example (in Git Bash or WSL):

  awk '{ print $1 }' file.txt

2. find

Linux:

• Typical Version: GNU find (from GNU Findutils).

• Features: Rich set of options (e.g., -maxdepth, -mtime, complex logical operators).

• Example:

  find /home/user -type f -name "*.txt"

macOS:

• Typical Version: BSD find.

• Differences: Some flags differ (for example, BSD find might not support -maxdepth or uses different syntax for time-based searches).

• Example:

  find /Users/username -type f -name "*.txt"

  (For advanced options, consult man find as macOS’s version may require different syntax.)

Windows:

• Availability: There is no direct equivalent in the native Command Prompt.

• Alternatives:

  • PowerShell: Use Get-ChildItem (alias gci) with filtering.

    Get-ChildItem -Path C:\Users\username -Filter *.txt -Recurse

  • Unix-like Environments: Install Cygwin, Git Bash, or use WSL to run GNU find.

3. grep and egrep

Linux:

• Typical Version: GNU grep (and egrep is equivalent to grep -E).

• Example:

  grep -E "error|fail" logfile.txt

• Note: GNU grep includes many advanced options and supports Perl-compatible regex (with -P).

macOS:

• Typical Version: BSD grep.

• Differences: Some advanced options may differ; for example, BSD grep might have slight differences in context flags or regex behavior.

• Example:

  grep -E "error|fail" logfile.txt

• Tip: For GNU grep on macOS, you can install it via Homebrew (often available as ggrep).

Windows:

• Availability: Not available natively.

• Alternatives:

  • findstr: A built-in Windows command that offers some similar capabilities (but with different regex syntax).

    findstr /R "error fail" logfile.txt

  • Unix-like Environments: Use Git Bash, Cygwin, or WSL to run GNU grep/egrep.

  • Example in Git Bash:

    grep -E "error|fail" logfile.txt

4. sed

Linux:

• Typical Version: GNU sed.

• Features: Rich feature set including in-place editing, extended regex support (with -r or -E), and many GNU-specific extensions.

• Example:

  sed -i 's/foo/bar/g' file.txt

macOS:

• Typical Version: BSD sed.

• Differences: The in-place edit option -i behaves differently; often you must supply a backup extension (or an empty string) like:

  sed -i '' 's/foo/bar/g' file.txt

• Example:
  The syntax is similar, but note the required argument to -i.

Windows:

• Availability: Not included in CMD by default.

• Alternatives:

  • Unix-like Environments: Use Cygwin, Git Bash, or WSL to run GNU sed.

  • Ports: There are native ports like GnuWin32 sed.

• Example in Git Bash:

  sed -i 's/foo/bar/g' file.txt

5. rsync

Linux:

• Typical Version: GNU rsync.

• Features: Optimized for fast synchronization, incremental transfers, and many options (like --delete, --partial, -z for compression).

• Example:

  rsync -av --delete /source/ /destination/

macOS:

• Typical Version: macOS includes a version of rsync (often an older BSD-based version).

• Differences: The pre-installed version might be older and missing some newer features. Many users install a newer version via Homebrew.

• Example:

  rsync -av --delete /Users/username/Documents/ /Volumes/Backup/Documents/

Windows:

• Availability: Not provided by default.

• Alternatives:

  • cwRsync: A native Windows port of rsync.

  • Cygwin/WSL: Use rsync from a Unix-like environment.

• Example (using cwRsync or in Git Bash/WSL):

  rsync -av --delete /cygdrive/c/Users/username/Documents/ /cygdrive/d/Backup/Documents/

6. cut

Linux:

• Typical Version: GNU cut.

• Example:

  cut -d',' -f2 file.csv

macOS:

• Typical Version: BSD cut.

• Differences: Generally behaves the same, though subtle differences in locale or interpretation of delimiters might exist.

• Example:

  cut -d',' -f2 file.csv

Windows:

• Availability: Not available in CMD.

• Alternatives:

  • Unix-like Environments: Use Git Bash, Cygwin, or WSL.

• Example (Git Bash):

  cut -d',' -f2 file.csv

7. tr

Linux:

• Typical Version: GNU tr.

• Example:

  echo "hello" | tr 'a-z' 'A-Z'

macOS:

• Typical Version: BSD tr.

• Differences: Usually similar to GNU tr for basic translations.

• Example:

  echo "hello" | tr 'a-z' 'A-Z'

Windows:

• Availability: Not provided natively.

• Alternatives:

  • Use in Git Bash/Cygwin/WSL:

    echo "hello" | tr 'a-z' 'A-Z'

8. head and tail

Linux:

• Typical Version: GNU head and tail.

• Example (head):

  head -n 10 file.txt

• Example (tail):

  tail -n 10 file.txt

macOS:

• Typical Version: BSD versions of head and tail.

• Differences: Options and behavior are almost identical for basic usage.

• Examples:

  head -n 10 file.txt tail -n 10 file.txt

Windows:

• Availability: Not provided natively in CMD.

• Alternatives:

  • PowerShell: Use Get-Content -TotalCount 10 for head and Get-Content -Tail 10 for tail.

    Get-Content file.txt -TotalCount 10 Get-Content file.txt -Tail 10

  • Git Bash/Cygwin/WSL: Provide GNU head and tail.

    head -n 10 file.txt tail -n 10 file.txt

9. egrep

Linux:

• Typical Version: GNU grep supports extended regex (where egrep is equivalent to grep -E).

• Example:

  egrep "foo|bar" file.txt

macOS:

• Typical Version: BSD grep, where egrep still exists but may be gradually deprecated in favor of grep -E.

• Example:

  egrep "foo|bar" file.txt

Windows:

• Availability: Not natively available.

• Alternatives:

  • Unix-like Environments: Use Git Bash/Cygwin/WSL.

  • Or use PowerShell’s regex features with Select-String:

    Select-String -Pattern "foo|bar" -Path file.txt

10. uniq

Linux:

• Typical Version: GNU uniq.

• Example:

  sort file.txt | uniq -c

macOS:

• Typical Version: BSD uniq.

• Differences: Generally similar in behavior to GNU uniq.

• Example:

  sort file.txt | uniq -c

Windows:

• Availability: Not provided in CMD.

• Alternatives:

  • Unix-like Environments: Use Git Bash/Cygwin/WSL.

• Example (Git Bash):

  sort file.txt | uniq -c

11. wc

Linux:

• Typical Version: GNU wc.

• Example:

  wc file.txt

macOS:

• Typical Version: BSD wc.

• Differences: Options are similar; minor differences may occur with encoding.

• Example:

  wc file.txt

Windows:

• Availability: Not provided in CMD.

• Alternatives:

  • Unix-like Environments: Use Git Bash/Cygwin/WSL.

  • PowerShell alternative: Use measures like (Get-Content file.txt).Count for line counts.

• Example (Git Bash):

  wc file.txt

12. cat

Linux:

• Typical Version: GNU cat.

• Example:

  cat file.txt

macOS:

• Typical Version: BSD cat.

• Differences: Functionality is essentially the same.

• Example:

  cat file.txt

Windows:

• Native Alternative: The built-in type command in CMD serves a similar purpose.

  type file.txt

• Alternatives:

  • PowerShell: Get-Content file.txt

  • Unix-like Environments: Git Bash/Cygwin/WSL provide GNU cat.

  • Example (PowerShell):

    Get-Content file.txt

13. The Pipe Operator (|)

Linux and macOS:

• Shells: Bash, Zsh, and other POSIX-compliant shells support the pipe operator natively.

• Example:

  ls -l | grep "^d" | wc -l

Windows:

• CMD: Supports the pipe operator (|), though the behavior of commands differs from Unix.

  dir /B | find /C /V ""

  (This counts the number of files using CMD’s built-in commands.)

• PowerShell: Uses the pipe operator (|) extensively. However, PowerShell pipes objects (not plain text) between commands.

  Get-ChildItem | Where-Object { $_.PSIsContainer } | Measure-Object | Select-Object -ExpandProperty Count

• Unix-like Environments: When using Git Bash/Cygwin/WSL, the pipe operator behaves as on Linux/macOS.

Conclusion

While the fundamental behavior of many classic Unix commands remains similar across Linux and macOS (with GNU vs. BSD variations being the most notable difference), Windows does not include these tools natively. Windows users can either rely on built-in alternatives (such as PowerShell cmdlets or the type and findstr commands) or install a Unix-like environment (via Cygwin, Git Bash, or WSL) to access the full power of these utilities.

Understanding these differences is essential when writing cross-platform scripts or migrating between environments. By paying attention to option differences (such as the -i flag in sed on macOS vs. Linux) and knowing the available alternatives on Windows, you can create robust, portable command-line workflows.

Further Reading and Resources

• Linux Documentation:

  • GNU Coreutils Manuals (e.g., GNU awk, GNU sed, etc.)

• macOS Documentation:

  • BSD Man Pages (accessible via man <command> in Terminal)

• Windows Alternatives:

  • Windows Subsystem for Linux (WSL)

  • PowerShell Cmdlet Reference

  • Cygwin and Git for Windows

• Community Resources:

  • Stack Overflow

  • The Art of Command Line

Experiment with these commands on your platform of choice, and consult the relevant documentation to fine-tune your scripts for portability and efficiency. Happy scripting!