SHELL

Shell Module in Vint

The Shell module in Vint provides a way to interact with the system's shell environment, allowing you to execute commands and check the existence of commands or files.

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Importing the Shell Module

To use the Shell module, import it as follows:

import shell

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Functions and Examples

1. Run a Shell Command (run)

The run function allows you to execute a shell command and capture its output.

Syntax:

run(command)

• command (string): The shell command to execute (e.g., echo Hello or ls).

Example:

import shell

output = shell.run("echo Hello, Shell!")
print(output)
// Output: "Hello, Shell!"

In the example, the echo command prints the string Hello, Shell! to the terminal, and the output is captured by shell.run and printed.

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2. Check if a Command Exists (exists)

The exists function checks whether a given command is available on the system.

Syntax:

exists(command)

• command (string): The name of the command to check (e.g., ls, python, echo).

Example:

import shell

exists_ls = shell.exists("ls")
print(exists_ls)
// Output: true if the 'ls' command exists

exists_python = shell.exists("python")
print(exists_python)
// Output: true if the 'python' command exists

exists_nonexistent = shell.exists("nonexistent_command")
print(exists_nonexistent)
// Output: false if the 'nonexistent_command' does not exist

In the example, exists("ls") checks if the ls command is available, returning true if it exists, and false otherwise.

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3. Running Commands with Parameters

You can also pass arguments to shell commands within the run function.

Example:

import shell

output = shell.run("ls -l")
print(output)
// Output: The list of files and directories in the current directory with detailed info.

This runs the ls command with the -l flag to list files and directories with additional details (e.g., permissions, size, etc.).

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Summary of Functions

Function	Description	Example Output
run	Executes a shell command and returns its output.	"Hello, Shell!"
exists	Checks if a command is available in the shell.	true or false depending on command existence

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The Shell module is a powerful tool for integrating system-level shell commands directly within your Vint programs. It is especially useful for automation tasks, system monitoring, or running external scripts.