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I started learning PHP the other day and can't understand the error. When i write code
header("Content-type: image/jpeg"); // и вообще пытаюсь послать любой заголовок
Warning: Cannot modify header information - headers already sent by// my script on the first line
Tell me, who sends headers (Apatch php or who)? And how do I completely control the output or disable the automatic sending of headers?