How to Install PHP cURL Extension on Linux: 5 Easy Steps

The cURL extension in PHP is a powerful tool that allows developers to make HTTP requests from their PHP scripts. Whether you’re interacting with APIs, scraping web pages, or downloading files, the cURL extension is an essential component for many web applications.

In this article, we will learn how to install PHP cURL extension on a Linux system. We’ll cover various methods, including installation via package managers like apt and yum, as well as manual compilation from the source.

Prerequisites

Before we begin, ensure that you have the following:

• A Linux-based operating system: This guide is tailored for Linux distributions such as Ubuntu, Debian, CentOS, and Fedora.
• PHP installed: You should have PHP installed on your system. If not, you can install it using your distribution’s package manager.
• Superuser (root) access: Some commands require administrative privileges, so you may need to use sudo or log in as the root user.

How to Install PHP cURL Extension on Linux

Step 1: Check if PHP cURL Extension is Already Installed

Before proceeding with the installation, it’s a good idea to check if the cURL extension is already installed and enabled on your system. You can do this by running the following command:

php -m | grep curl

If you see curl in the output, the extension is already installed and enabled. If not, proceed to the next steps.

Step 2: Install PHP cURL Extension on Ubuntu/Debian

Ubuntu and Debian-based distributions use the apt package manager. Follow these steps to install the PHP cURL extension:

Update the Package List

First, update your package list to ensure you have the latest information about available packages:

sudo apt update

Install the PHP cURL Extension

Next, install the PHP cURL extension using the following command:

sudo apt install php-curl

This command will install the cURL extension for the default PHP version on your system. If you have multiple PHP versions installed, you may need to specify the version:

sudo apt install php7.4-curl

Replace php7.4 with the appropriate PHP version.

Restart the Web Server

After installing the extension, restart your web server (Apache or Nginx) to apply the changes:

For Apache:

sudo systemctl restart apache2

For Nginx:

sudo systemctl restart nginx

Verify the Installation

Finally, verify that the cURL extension is installed and enabled:

php -m | grep curl

You should see curl in the output.

Step 3: Install PHP cURL Extension on CentOS/Fedora

CentOS and Fedora-based distributions use the yum or dnf package manager. Follow these steps to install the PHP cURL extension:

Update the Package List

First, update your package list:

sudo yum update

Or, if you’re using Fedora:

sudo dnf update

Install the PHP cURL Extension

Next, install the PHP cURL extension using the following command:

sudo yum install php-curl

Or, for Fedora:

sudo dnf install php-curl

This command will install the cURL extension for the default PHP version on your system. If you have multiple PHP versions installed, you may need to specify the version:

sudo yum install php74-php-curl

Replace php74 with the appropriate PHP version.

Restart the Web Server

After installing the extension, restart your web server (Apache or Nginx) to apply the changes:

For Apache:

sudo systemctl restart httpd

For Nginx:

sudo systemctl restart nginx

Verify the Installation

Finally, verify that the cURL extension is installed and enabled:

php -m | grep curl

You should see curl in the output.

Step 4: Install PHP cURL Extension from Source

If you prefer to compile PHP from source or if your distribution’s package manager does not provide the cURL extension, you can install it manually. This method is more advanced and requires some familiarity with compiling software on Linux.

Install Required Dependencies

First, install the necessary dependencies for compiling PHP and the cURL extension:

For Ubuntu/Debian:

sudo apt install build-essential libcurl4-openssl-dev php-dev php-pear

For CentOS/Fedora:

sudo yum groupinstall "Development Tools"
sudo yum install libcurl-devel php-devel php-pear

Download and Extract the PHP Source Code

Next, download the PHP source code from the official PHP website. Replace 7.4.0 with the version you want to install:

wget https://www.php.net/distributions/php-7.4.0.tar.gz
tar -xvzf php-7.4.0.tar.gz
cd php-7.4.0/ext/curl

Compile the cURL Extension

Now, compile the cURL extension using the following commands:

phpize
./configure
make
sudo make install

Enable the cURL Extension

After compiling, you need to enable the cURL extension in your PHP configuration. Open your php.ini file:

sudo nano /etc/php/7.4/cli/php.ini

Add the following line to enable the cURL extension:

extension=curl.so

Save and close the file.

Restart the Web Server

Restart your web server to apply the changes:

For Apache:

sudo systemctl restart apache2

For Nginx:

sudo systemctl restart nginx

Verify the Installation

Finally, verify that the cURL extension is installed and enabled:

php -m | grep curl

You should see curl in the output.

Step 5: Troubleshooting

If you encounter any issues during the installation process, consider the following troubleshooting steps:

Check PHP Version

Ensure that you are installing the cURL extension for the correct PHP version. You can check your PHP version using:

php -v

Check Web Server Logs

If the cURL extension is not working after installation, check your web server logs for any error messages. For Apache, the logs are typically located at /var/log/apache2/error.log. For Nginx, they are usually at /var/log/nginx/error.log.

Verify php.ini Configuration

Ensure that the extension=curl.so line is correctly added to your php.ini file. You can also check the loaded configuration using:

php --ini

Reinstall the Extension

If all else fails, try reinstalling the cURL extension:

sudo apt remove php-curl
sudo apt install php-curl

Or, for CentOS/Fedora:

sudo yum remove php-curl
sudo yum install php-curl

Conclusion

Installing the PHP cURL extension on Linux is a straightforward process that can be accomplished using your distribution’s package manager or by compiling from source. Whether you’re using Ubuntu, Debian, CentOS, or Fedora, the steps outlined in this guide should help you successfully install and enable the cURL extension for your PHP environment.

By following this guide, you should now have the PHP cURL extension installed and ready to use on your Linux system. This powerful tool will enable you to make HTTP requests, interact with APIs, and perform a wide range of web-related tasks from your PHP scripts. Happy coding!