PHP | rewind( ) Function

The rewind() function in PHP is an inbuilt function which is used to set the position of the file pointer to the beginning of the file.
Any data written to a file will always be appended if the file is opened in append (“a” or “a+”) mode regardless of the file pointer position.
The file on which the pointer has to be edited is sent as a parameter to the rewind() function and it returns True on success or False on failure.

Syntax:

rewind(file)

Parameters Used:
The rewind() function in PHP accepts one parameter.

• file : It is a mandatory parameter which specifies the file to be edited.

Return Value:
It returns True on success or False on failure.

Errors And Exception:

1. The rewind() function generates an E_WARNING level error on failure.
2. The stream must be “seekable” for using the rewind() function.
3. If the file is opened in append mode, the data written will be appended regardless of the position of the pointer.

Examples:

Input: $myfile = fopen("gfg.txt", "r");
        fseek($myfile, "10");
        rewind($myfile);
        fclose($file);

Output: 1

Input : $myfile = fopen("gfg.txt", "r+");
        fwrite($myfile, 'geeksforgeeks');
        rewind($myfile);
        fwrite($myfile, 'portal');
        rewind($myfile);
        echo fread($myfile, filesize("gfg.txt"));
        fclose($myfile);

Output : portalforgeeks
Here all characters of the file as it is after rewind "portal"

Below are the programs to illustrate the rewind() function.

Program 1

Output:

1

Program 2

Output:

geeksportalks a computer science portal

Reference:
http://php.net/manual/en/function.rewind.php

Shubrodeep Banerjee

I am a technology enthusiast who has a keen interest in programming I am pursuing Engineering in Computer Science from GEU, Dehradun I like to unwind by watching movies and English sitcomsI have a keen interest in music