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Files II

Most of the time you will not know how many lines there are in a file. This page will show you a way of handling this situation.

1. Create a new file in the ~YOURID/PHP/ directory by executing the following from the Command Line.

   cd; cd PHP; ls -l > dir_list.dat

   This will get you into the desired directory and create a file called dir_list.dat which will contain the long version of the directory listing.

2. Create the following script in the same directory.

   <?php
   // listfile.php
   // Purpose: read all lines from a file
   //     and print them
   
   // Open the file for reading 
   $fp = fopen( "dir_list.dat", "r") or die("No such file!\n");
   
   // Read lines one by one, printing each out in turn
   while ( !feof($fp) ) {
      $str = fgets( $fp, 500);
      echo $str;
   }
   
   // Close the file
   fclose($fp);
   ?>
   

3. Run the script. The output should be the same if you execute the following on the Command Line.

   cat dir_list.dat

Notes

• The built-in function feof returns TRUE if there is no more data or if some other error occurs. This works the same as the function EOF in Pascal.
• The bang character (!) in the while condition is the logical NOT operator.