Installing PHP for Mac M1: A Step-by-Step Guide

If you're trying to install PHP 7.4 on your brand-new MacBook Pro with an M1 chip, you might have encountered the error 'Cannot install under Rosetta 2 in ARM default prefix (/opt/homebrew)!' when running `brew install`. This is because Rosetta 2, which helps bridge the gap between Intel-based software and Apple's new ARM64 architecture, isn't compatible with PHP 7.4.

To resolve this issue, you'll need to specify the architecture first. One way to do this is by using the `arch` command to switch to the ARM architecture before installing PHP 7.4. Here's how:

1. Restart your terminal and verify that your PHP version is set correctly. You can do this by running `php -v`. If you don't have PHP installed, you'll need to add it to your PATH environment variable. To do this, open your `.zshrc` file (which is usually found in your home directory) and add the following lines:

```

echo 'export PATH='/opt/homebrew/opt/php/bin:$PATH'' > ~/.zshrc

echo 'export PATH='/opt/homebrew/opt/php/sbin:$PATH'' > ~/.zshrc

```

Then, restart your terminal to apply these changes.

2. Once you've verified that your PHP version is correct, it's time to install PHP 7.4 using Homebrew. To do this, run the following command:

```

arch -arm64 brew install php@7.4

```

This will install PHP 7.4 on your M1 chip-compatible architecture.

3. If you need to rerun a command under ARM architecture, simply use the `arch` command again with the `-arm64` flag. For example:

```

arch -arm64 brew install

```

Homebrew makes managing packages on macOS easy by providing a simple way to install and manage software packages. With its vast repository of packages, you can quickly find and install the tools and utilities you need for your development workflow.

By following these steps, you should be able to successfully install PHP 7.4 on your Mac M1 without encountering any issues related to Rosetta 2 or architecture compatibility. Happy coding!

Php for mac m1