Prepending Files in PHP
When writing to a file in PHP, data is typically appended to the end of the existing file. However, there are scenarios where it may be necessary to prepend content to the beginning of the file.
One way to achieve this is to use the rewind() function to move the file pointer to the beginning of the file, ensuring that any subsequent writes will overwrite the existing content. However, this approach is not recommended for larger files, as it can result in data loss if the new content is larger than the existing file.
A more reliable method involves prepending the new content to the existing file contents before overwriting the file. This can be achieved using the following code:
$prepend = 'prepend me please'; $file = '/path/to/file'; $fileContents = file_get_contents($file); file_put_contents($file, $prepend . $fileContents);
In this example, the file_get_contents() function is used to retrieve the existing file contents, and the file_put_contents() function is used to overwrite the file with the prepended content. By concatenating the new content with the original file contents before overwriting, the new content will be written to the beginning of the file, effectively prepending it.
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