In this tutorial, I am going to show you a simple way to write a Hit Counter script in PHP to save and display the number of visits to your website. We will basically store and increment the hits in a file, that can be used to display the total hit count as well. The… Read More »
A port scanner is a program designed to probe a server or host for open ports. Looking at open ports, one can tell what services might be running on the remote server. We earlier made a TCP Connect port scanner in C here – https://www.binarytides.com/tcp-connect-port-scanner-code-c-winsock/ and here – https://www.binarytides.com/tcp-connect-port-scanner-c-code-linux-sockets/ Now we shall try making the… Read More »
The getimagesize function of php provides lot of information about an image file , including its type. The type can be used to check if the file is a valid image file or not. To check if a file is an image or not, use the function function is_image($path) { $a = getimagesize($path); $image_type =… Read More »
In many php applications there are multiple tasks that need to be run via cron at different times. In a typical application you may be doing the following tasks via cronjobs : 1. Backup database. 2. Send out email to subscribers. 3. Clear temporary files. 4. Fetch xml feeds from some source and store them… Read More »
desktop:~$ php -a Interactive shell php > echo time(); 1319362432 php > Above is an example of a given timestamp. And a cron schedule can look like this 0 5 * * * – which means run everyday at 5 hours and 0 minutes. Now in a php application you may need to test if… Read More »
The strtotime function is used to convert a date in various formats to a timestamp. However its behaviour is different based on architecture it is running on, whether 32bit or 64bit. Lets take a few examples : In 64 bit environment desktop:~$ php -a Interactive shell php > echo strtotime("0000-00-00 00:00:00"); -62170005200 php > echo… Read More »
The autoincrement feature in mysql allows us to create numeric fields that automatically increment by 1 for every row inserted. It does it atomically so we don’t have to worry about any duplicates or collision. However, there are situations when we need an autoincrement field to reset at regular intervals like every month or so…. Read More »
If a file is to be saved in at path /var/www/a/b/c/d/abc.zip where the directory c and d dont exist then the directories have to created. Here is a function that uses recursion to check for directories in a path and create them if they do not exist : /** Make a nested path , creating… Read More »
PHP’s session_start method stores the session data in files by default. These files are stored in the tmp directory of the OS and are cleared at intervals by the garbage collector. Alternatively the session data can be stored in database as well. Storing session data in database has certain advantages : 1. Limit the number… Read More »
Php from command line PHP scripts are usually opened in a web browser. But they can be run from command line or terminal as well. The syntax to run a script from commandline is very much similar to python or perl. php /path/to/script/index.php Inside a script it might be necessary to test if it is… Read More »