What is cURL and How to Use It with Proxy?

If you are already familiar with different developer tools, you may know how effective cURL is. You can exchange data between devices and servers using this text tool. Especially when you use backconnect proxy servers, cURL can be of great use.

So, what is it and how do you use cURL with a proxy? Well, this guide on using cURL with proxy can help you a lot in understanding the concept and performing different operations. For now, let’s explore what cURL is and how you can use it in various cases.

What Is cURL?

cURL or client URL (written cURL, but pronounced curl) is a powerful command line tool that helps you exchange data through the URL. All modern operating systems have cURL built-in and you can use it through the command line interface.

When users specify a URL, cURL can perform different operations like downloading data from that URL, sending specific data to a server URL, and more. You can also test proxies by sending HTML requests using cURL, which we will discuss a bit later.

How Does cURL Work?

If you look at the most basic cURL syntax, it looks like the following.

• cURL [options] [URL]

After cURL, the first section refers to the method you will be using. For example, you can use a GET method to parse data from a server URL. Alternatively, you can use the POST method to send data to the specified server. Different options can also be used with the options to specify what you want cURL to display.

For example, you can use -X after the method to specify that the connection will use a proxy server. Various alternatives for options are available here and you will gradually become familiar with them.

How to Use cURL with Proxy?

You can perform a variety of tasks using cURL with proxy. Here is a detailed overview of the tasks.

Checking the IP Address of Proxy Server Info

When you already have a proxy server set up, you can perform the following cURL commands to check your IP address or other information about your proxy server.

If you write cURL ipinfo.io, it will return the IP address being used currently. Besides, it can parse other information, like your location, ISP, time zone, etc.

Even if you don’t have a proxy server set up on your machine, you can use the following commands to check if a proxy is being used in your requests.

• curl -x 0.0.0.0:80 ipinfo.io

Here, the first four digits separated by dots after -x is the IP address of the proxy server. The number after the colon is the port number of the proxy server. Instead of this command, you can directly use the URL or domain name of the proxy server to check its info.

Using cURL with Different Proxies

cURL supports more than 20 protocols, including HTTPS, SOCKS, POP3, SMTP, etc. By default, it will use the HTTP protocol. When using cURL with a specific protocol, you need to write that before the domain name and after the option.

For example, you can use the following cURL command.

• cURL -x socks5://exampleurl.com

Different Methods in cURL

As we have already mentioned, you can use multiple methods in cURL. Here is how to make different requests using cURL commands.

GET Method

This is used to parse information from a server URL. A basic command for the GET method will look like this.

• cURL https://exampleurl.com

Or you can specify the GET method by writing it as the following.

• cURL -X GET https://exampleurl.com

POST Method

You can use this method to send data to a server. For this method, you need to include the POST method after -X to specify the purpose. Then, you can specify the data you want to send to the server. A basic POST method syntax will look like the following.

• cURL -X POST “data” https://exampleurl.com

Use Cases of cURL

cURL has a wide variety of use cases where you can request and transfer data without the help of intuitive interfaces of API. Here is a quick list.

Checking Proxies

When using a backconnect proxy server, it can be necessary to check different proxy parameters. Without using any third-party tool or APIs, you can directly check that from the terminal.

Downloading Files

Just like you would download something to your device from the browser, you can use cURL to download items like images or files. cURL will save the downloaded item to the specified directory.

Final Thoughts

cURL is a powerful command line tool that gives you access to various information through the server URL. Besides parsing and downloading data, you can also send data to servers through the URL.

It has different methods to perform desired operations. You just need to understand how cURL works and know its syntax to use it in your favor.