PHP File I/O

Reading Files

// Read entire file
$content = file_get_contents("data.txt");

// Read line by line
$handle = fopen("data.txt", "r");
while (($line = fgets($handle)) !== false) {
    echo $line;
}
fclose($handle);

Writing Files

file_put_contents("output.txt", "Hello, World!");

// Append mode
$handle = fopen("log.txt", "a");
fwrite($handle, "New entry
");
fclose($handle);

File Functions

file_exists($path);  // Check if file exists
filesize($path);      // Get file size
unlink($path);        // Delete file
rename($old, $new);   // Rename/move

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