Contacting iphone software update server PHP code showing client IP and server IP

Let’s take a look at the code:

Copy the code The code is as follows:

echo "(1) The IP address of the user browsing the current page is: ";
echo $_SERVER['REMOTE_ADDR'];
echo "
";
echo "(2) The IP address of the user browsing the current page is: ";
echo getenv('REMOTE_ADDR');
echo "
";
echo "Host The IP address of www.baidu.com is: ";
echo gethostbyname(www.baidu.com);

its The output result is:
(1) The IP address of the user browsing the current page is: 127.0.0.1
(2) The IP address of the user browsing the current page is: 127.0.0.1
The IP address of the host www.baidu.com is: 61.135.169.105
There are two ways to get the client's IP address:
The first is to use:
?$_SERVER['REMOTE_ADDR']
It is browsing the IP address of the user on the current page, and the output here is 127.0.0.1 , because this is a local test, the output is my local loop address.
The second one is to use:
?getenv('REMOTE_ADDR')
The function getenv is used here: Gets the value of an environment variable (gets the value of various environment variables), return value: Returns the value of the environment variable varname , or FALSE on an error (returns FALSE if it fails).
About getting the IP address of the server:
?gethostbyname(www.baidu.com)
The function gethostbyname is used here: Get the IP address corresponding to a given Internet host name (get its IP address through a given host name), return value: Returns the IP address of the Internet host specified by hostname or a string containing the unmodified hostname on failure (returns the original input character hostname on failure).
Pay attention to the last sentence here, that is, if it fails, it will output the original, for example:
?echo "Invalid The IP address of the host iwilldown is: ";
echo gethostbyname("iwilldown");
Output:
?The IP address of the invalid host iwilldown is: iwilldown
Of course, this is not an IP address...

The above introduces the PHP code for displaying the client IP and server IP of the iPhone software update server, including the content of the iPhone software update server. I hope it will be helpful to friends who are interested in PHP tutorials.