This error occurs when child_process.execFile() attempts to execute a script file that lacks executable permissions. The Node.js process cannot spawn the file as a child process because the operating system denies execution.
The "execFile() permission denied" error happens when you use Node.js's `child_process.execFile()` method to run a script file that doesn't have executable permissions set at the operating system level. Unlike `exec()`, which spawns a shell, `execFile()` attempts to execute the file directly as a new process. On Unix-based systems (Linux, macOS), this requires the file to have the executable bit set in its permissions. Without this permission, the operating system prevents the file from being executed, resulting in an EACCES (Access Denied) error. This error is specific to the `execFile()` method and doesn't occur with `exec()` because `exec()` spawns a shell that interprets the script, while `execFile()` attempts direct execution for better efficiency.
Check the current permissions of your script file:
ls -l /path/to/your/script.shLook for the permissions string (e.g., -rw-r--r--). If there's no x in the string, the file is not executable.
Make the script executable for the owner:
chmod +x /path/to/your/script.shOr set specific permissions (read, write, execute for owner; read, execute for group and others):
chmod 755 /path/to/your/script.shVerify the change:
ls -l /path/to/your/script.sh
# Should show: -rwxr-xr-xEnsure your script has a proper shebang at the top to specify the interpreter:
#!/bin/bash
# or
#!/usr/bin/env node
# or
#!/usr/bin/env python3This tells the system which interpreter to use when executing the file directly.
Execute the script with proper error handling:
const { execFile } = require('child_process');
execFile('/path/to/your/script.sh', ['arg1', 'arg2'], (error, stdout, stderr) => {
if (error) {
if (error.code === 'EACCES') {
console.error('Permission denied. Ensure the script has executable permissions.');
console.error('Run: chmod +x /path/to/your/script.sh');
}
console.error('Error:', error);
return;
}
console.log('Output:', stdout);
});For shell scripts that need a shell context, consider using exec() instead:
const { exec } = require('child_process');
exec('sh /path/to/your/script.sh', (error, stdout, stderr) => {
// This works regardless of executable permissions
});On Windows, .bat and .cmd files cannot be executed with execFile() directly. Use spawn with shell option or exec:
const { spawn } = require('child_process');
// For Windows batch files
const child = spawn('script.bat', [], { shell: true });
// Or use exec
const { exec } = require('child_process');
exec('script.bat', (error, stdout, stderr) => {
// Handles Windows batch files correctly
});Security Considerations: Using execFile() is generally more secure than exec() because it doesn't spawn a shell, reducing the risk of shell injection attacks. However, you must ensure proper input validation when passing arguments to the executed file.
Directory Mount Options: If your script is on a mounted filesystem, check for the noexec flag:
mount | grep /path/to/mountIf noexec is set, executables cannot run from that filesystem. You'll need to remount without noexec or move the script to a different location.
Ownership and Group Permissions: In multi-user environments, ensure the Node.js process runs as a user with appropriate permissions. You may need to adjust ownership:
chown username:groupname /path/to/script.sh
chmod 750 /path/to/script.sh # Owner can execute, group can read/executeAlternative: Use spawn with shell: If you need shell features (pipes, redirects, etc.), use spawn() with the shell option instead of execFile():
const { spawn } = require('child_process');
const child = spawn('your-script.sh', [], { shell: true });CI/CD Pipelines: In Docker containers or CI environments, ensure your build process sets executable permissions. Add to your Dockerfile:
COPY scripts/my-script.sh /app/scripts/
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