2024-02-07
Before diving into enable, let’s clarify what shell built-ins are. Unlike external commands (which are separate executables), built-in commands are essential parts of the shell itself. They’re typically faster and more efficient because they don’t require the shell to fork a new process to execute them. Common examples include cd, exit, echo, and many more.
enable Command: Bringing Built-ins Back to LifeThe enable command reactivates shell built-in commands that have been disabled. This is particularly useful when you’ve accidentally or intentionally disabled a command and need to restore its functionality. It takes a single argument: the name of the built-in command to enable.
Example 1: Enabling a Disabled Built-in
Let’s say, for demonstration purposes, we’ve disabled the echo command (a highly unlikely scenario in practice, but useful for illustration):
``bash ## Thedisable` Command: Temporarily Removing Built-ins
The companion command, disable, works in the opposite manner. It temporarily removes a built-in command from the shell’s available commands. The effect is reversed by using enable.
Example 3: Disabling and Re-enabling a Built-in
Let’s disable and then re-enable the cd command (again, for illustrative purposes; disabling cd would severely limit your shell interaction):
```bash disable cd
The enable and disable commands offer a powerful mechanism for customizing your shell environment. While disabling core commands like cd or exit is generally not recommended (it can severely impact usability), they provide control over less frequently used built-ins or for experimentation and troubleshooting. Remember that the effects of disable are only temporary and persist only for the current shell session. Closing and reopening the terminal will reset the built-in command status.
TODELETE