File content is not available after fputcsv-CodePudding

Please explain to me why the function file_get_contents returns the contents of the file, while fread does not. How can I read file content after fputcsv?

$file = fopen('test.txt', 'r ');
fputcsv($file, [1, 2, 4]);
var_dump(fread($file, 1024));
var_dump(file_get_contents('test.txt'));

CodePudding user response：

fread() reads from the current position in the file stream, which is after what you just wrote. You need to seek to the beginning to read the file.

$file = fopen('test.txt', 'r ');
fputcsv($file, [1, 2, 4]);
fseek($file, 0);
var_dump(fread($file, 1024));