How can shell access the return value of curl?

In shell, you can use the following method to retrieve the return value of the curl command:

1. The $? variable holds the exit status code of the previous command, typically used to check if the command executed successfully. When the curl command is successful, its exit status code is 0, which can be obtained using the $? variable.
2. Retrieve the response from https://example.com using curl command and store the result in a variable. Display the curl return value as: $result.
3. With the -c parameter, the curl command can save the returned result to a file, allowing you to determine the success of the curl command by checking if the file exists.
4. Save the output of the curl command to result.txt file and check if the file exists. If it does, output “curl executed successfully”, otherwise output “curl failed to execute”.
5. By using the -o parameter, the curl command can save the results to a file, allowing you to check the file’s content to determine if the curl command was successful.
6. Download the content from https://example.com and save it as result.txt. If the file size is greater than zero, then print “curl execution successful”, otherwise print “curl execution failed”.

The above are some common methods, you can choose the appropriate way to obtain the return value of the curl command according to specific needs.