How to use php fseek function

php The fseek() function is used to locate the file pointer. Its syntax is [fseek(file,offset,whence)]. The parameter file is required and refers to the file to be located; offset is required and refers to the file to be located. Specifies the new position, measured in bytes from the beginning of the file.

php fseek function usage:

php fseek() function syntax

Function: Locate within an open file.

Syntax:

fseek(file,offset,whence)

Parameters:

file Required. Specifies the file to locate in.

offset Required. Specifies the new position (measured in bytes from the beginning of the file).

whence Optional. Possible values: SEEK_SET - Set position equal to offset bytes. default. SEEK_CUR - Sets the position to the current position plus offset. SEEK_END - Sets the position to the end of the file plus offset (to move to a position before the end of the file, offset must be a negative value).

Description:

This function moves the file pointer forward or backward from the current position to a new position. The new position is measured in bytes starting from the file header. . Returns 0 on success; otherwise returns -1. Note that moving to a position after EOF does not produce an error.

php fseek() function usage example

<?php
$file = fopen("./test.txt","r");
// 输出当前位置
echo ftell($file);
echo "<br>";
// 改变当前位置
fseek($file,"13");
// 再次输出当前位置
echo ftell($file);
?>

This article is an introduction to the PHP fseek function. I hope it will be helpful to friends in need!

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