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fdatasync

(PHP 8 >= 8.1.0)

fdatasync — Synchronizes data (but not meta-data) to the file

Description

fdatasync(resource $stream): bool

This function synchronizes stream contents to storage media, just like fsync() does, but it does not synchronize file meta-data. Note that this function is only effectively different in POSIX systems. In Windows, this function is aliased to fsync().

Parameters

stream

The file pointer must be valid, and must point to a file successfully opened by fopen() or fsockopen() (and not yet closed by fclose()).

Return Values

Returns true on success or false on failure.

Examples

Example #1 fdatasync() example

<?php

$file = 'test.txt';

$stream = fopen($file, 'w');
fwrite($stream, 'test data');
fwrite($stream, "\r\n");
fwrite($stream, 'additional data');

fdatasync($stream);
fclose($stream);
?>

See Also

  • fflush() - Flushes the output to a file
  • fsync() - Synchronizes changes to the file (including meta-data)

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Licensed under the Creative Commons Attribution License v3.0 or later.
https://www.php.net/manual/en/function.fdatasync.php