How to Use the Command `brew list` (with Examples)

brew list is an integral command for users of Homebrew, a popular package manager for macOS and Linux. This command provides a systematic way to view what you have installed on your system, whether it be formulae (software packages) or casks (macOS applications). Understanding the brew list command can aid in system organization, maintenance, and troubleshooting.

Use Case 1: List All Installed Formulae and Casks

Code:

brew list

Motivation: This command is essential for users who need a comprehensive overview of all the software currently installed via Homebrew. When managing software installations, it’s crucial to know exactly what is occupying your disk space and potentially affecting your system performance.

Explanation:

• brew: Refers to the Homebrew package manager.
• list: Tells Homebrew to display all installed formulae and casks, essentially everything you have installed via the package manager.

Example Output:

app1
app2
package1
package2

The output is a simple list of all the Homebrew-managed applications and packages on your system, providing a quick glance at your current setup.

Use Case 2: List Files Belonging to an Installed Formula

Code:

brew list formula

Motivation: When you need to inspect the specific files that make up a particular software package, this command proves invaluable. It can help in debugging, modifying, or understanding the structure of an installed formula.

Explanation:

• brew: Again, this indicates the use of the Homebrew package manager.
• list: Instructs the command to show file details.
• formula: Replace this with the specific name of the installed formula to see the files it comprises.

Example Output:

/usr/local/Cellar/formula/1.0.0/bin/executable
/usr/local/Cellar/formula/1.0.0/lib/library.dylib
/usr/local/Cellar/formula/1.0.0/share/doc/readme.md

The output lists all files associated with the installed formula, organized by their directory structure.

Use Case 3: List Artifacts of a Cask

Code:

brew list cask

Motivation: For users wanting to understand where a cask application puts its files on the system, this command is particularly helpful. It simplifies the task of tracking an application’s footprint for maintenance or removal purposes.

Explanation:

• brew: Represents the Homebrew package manager.
• list: Commands the system to display cask-specific data.
• cask: Replace this with the name of the cask whose artifacts you want to identify.

Example Output:

/Applications/CaskApp.app
/usr/local/Caskroom/cask/0.0.1/

This output allows the user to see where the application and its components reside within the system directory.

Use Case 4: List Only Formulae

Code:

brew list --formula

Motivation: When you are only interested in the command-line utilities and libraries installed, this command provides a targeted list of formulae, differentiating from applications with GUIs.

Explanation:

• brew: Signifies the Homebrew ecosystem.
• list: Directs to generate a listing.
• --formula: A flag that limits the output to formulae, excluding casks.

Example Output:

formula1
formula2

The output gives a clean list of terminal-based packages, aiding in tasks like bulk updating or uninstalling.

Use Case 5: List Only Casks

Code:

brew list --cask

Motivation: Focusing solely on GUI applications managed by Homebrew, this command helps users quickly identify installed applications that might need attention for updating or possible conflicts.

Explanation:

• brew: As always, references the Homebrew framework.
• list: Initiates a listing command.
• --cask: This flag filters the results to only include casks.

Example Output:

cask-app1
cask-app2

Users receive a precise list of installed GUI applications, distinct from command-line tools.

Use Case 6: List Only Pinned Formulae

Code:

brew list --pinned

Motivation: Users who deliberately keep certain packages at specific versions to ensure stability or compatibility will find this command particularly useful. It brings awareness to which software requires careful management during updates.

Explanation:

• brew: Represents interfacing with Homebrew.
• list: Triggers the listing functionality.
• --pinned: This argument specifically targets and lists formulae that the user has pinned to a particular version.

Example Output:

pinned-formula1
pinned-formula2

With this command, users can quickly review their pinned packages, assisting in maintaining system stability and managing customized software environments.

Conclusion:

The brew list command is a powerful tool within the Homebrew ecosystem, offering detailed insights into package management. Each variant of the command serves a specific purpose, enhancing user control and understanding of software installations on their systems. By employing these command examples, Homebrew users can efficiently manage and maintain their installed software, ensuring an organized and streamlined system environment.