How do you print received cookie info to stdout with curl?

When using the curl command, you can follow these steps to print the cookies received from the server to the standard output (stdout):

1. Use the -v or --verbose option: This option makes curl provide detailed information, including request and response headers. Cookies are typically included in the response headers.

2. Redirect or filter the output: While the -v option outputs extensive information, if you only need the cookie information, it may be necessary to use other tools (such as grep) to filter the output.

Here is a specific example demonstrating how to use curl combined with the grep command to print only the cookie information:

bash
curl -v http://example.com 2>&1 | grep 'Set-Cookie'

Here's a breakdown of the command:

• curl -v http://example.com: Sends a request to http://example.com in verbose mode.
• 2>&1: Redirects stderr to stdout, as curl's verbose output is sent to stderr.
• | grep 'Set-Cookie': Pipes the output to grep, which filters lines containing 'Set-Cookie', typically where cookie information is found.

This method directly outputs any Set-Cookie response header to the console, displaying the cookies sent by the server.

This method is suitable for debugging or testing to understand how the server sets cookies. When handling cookies in production environments, ensure compliance with relevant privacy policies and regulations.