Php-Null character

PHP Security-file system security-Null character problem because PHP file system operations are based on C-language functions, it may handle Null characters in unexpected ways. The Null character is used in the C language to mark the end of a string. a complete string starts with it and ends with a Null character. The following code demonstrates a similar attack:

Example #1 code that will be attacked by Null characters

Therefore, any string used for operating the file system (especially the string entered outside the program) must be properly checked. The following is an improved version of the preceding example:

Example #2 verify the correct input practices