PHP | ftell( ) Function

The ftell() function in PHP is an inbuilt function which is used to return the current position in an open file. The file is sent as a parameter to the ftell() function and it returns the current file pointer position on success, or FALSE on failure.
Syntax: 
 

ftell( $file )

Parameters Used: The ftell() function in PHP accepts only one parameter $file. It is a mandatory parameter which specifies the file.
Return Value: It returns the current file pointer position on success, or FALSE on failure.
Exceptions: 
 

1. Some filesystem functions may return unexpected results for files which are larger than 2GB since PHP's integer type is signed and many platforms use 32bit integers.
2. When opening a file for reading and writing via fopen('file', 'a+') the file pointer should be at the end of the file.

Examples: 
 

Input : $myfile = fopen("gfg.txt", "r");
 echo ftell($myfile);
Output : 0

Input : $myfile = fopen("gfg.txt", "r");
 echo ftell($myfile);
 fseek($myfile, "36");
 echo ftell($myfile);
Output : 0
 36

Below programs illustrate the ftell() function:
Program 1: In the below program the file named gfg.txt contains the following content. 
 

Geeksforgeeks is a portal for geeks! 
 

Output: 
 

0

Program 2: In the below program the file named gfg.txt contains the following content. 
 

Geeksforgeeks is a portal for geeks! 
 

Output: 
 

0
36

Reference: https://www.php.net/manual/en/function.ftell.php