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# fseek

(PHP 3, PHP 4, PHP 5)

fseek -- Seeks on a file pointer

## Description

int fseek ( resource handle, int offset [, int whence] )

Sets the file position indicator for the file referenced by `handle`. The new position, measured in bytes from the beginning of the file, is obtained by adding `offset` to the position specified by `whence`, whose values are defined as follows:

`SEEK_SET` - Set position equal to `offset` bytes.
`SEEK_CUR` - Set position to current location plus `offset`.
`SEEK_END` - Set position to end-of-file plus `offset`. (To move to a position before the end-of-file, you need to pass a negative value in `offset`.)

If `whence` is not specified, it is assumed to be `SEEK_SET`.

Upon success, returns 0; otherwise, returns -1. Note that seeking past EOF is not considered an error.

Example 1. fseek() example

`<?php $fp = fopen('somefile.txt', 'r'); // read some data $data = fgets($fp, 4096); // move back to the beginning of the file // same as rewind($fp); fseek($fp, 0); ?>`

May not be used on file pointers returned by fopen() if they use the "http://" or "ftp://" formats. fseek() gives also undefined results for append-only streams (opened with "a" flag).

> Note: The `whence` argument was added after PHP 4.0.0.

> Note: If you have opened the file in append ("a" or "a+") mode, any data you write to the file will always be appended, regardless of the file position.

See also ftell() and rewind().

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