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:
- 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.
- 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.
Geeksforneveropen is a portal for neveropen!
php
<?php// Opening a file in read. mode$myfile = fopen("gfg.txt", "r");// displaying the current position of the pointer in the opened fileecho ftell($myfile);// closing the filefclose($myfile);?> |
Output:
0
Program 2: In the below program the file named gfg.txt contains the following content.
Geeksforneveropen is a portal for neveropen!
php
<?php// Opening a file in read. mode$myfile = fopen("gfg.txt", "r");// displaying the current position of the pointer in the opened fileecho ftell($myfile);// changing current positionfseek($myfile, "36");//displaying current positionecho "<br />" . ftell($myfile);// closing the filefclose($myfile);?> |
Output:
0 36
Reference: http://php.net/manual/en/function.ftell.php
