How to Ensure Immediate Output Flushing in PHP After Each `echo` Call?

Achieving Output Flushing After Each echo Call

When utilizing PHP scripts for logging purposes, it's crucial to ensure that output is transmitted to the client as soon as it's generated. This prevents the page from appearing blank during script processing.

Failed Attempts with ob_start() and ob_flush()

Despite attempts with ob_start() and ob_flush(), the output is not immediately sent to the client. This indicates a potential PHP or Apache configuration issue.

Optimal Solution: Specifying Character Set

To resolve this issue, it's necessary to specify a character set when using ob_flush(). Here's an example that worked:

header( 'Content-type: text/html; charset=utf-8' );
echo 'Begin ...<br />';
for( $i = 0 ; $i < 10 ; $i++ )
{
    echo $i . '<br />';
    ob_flush();
    flush();
    sleep(1);
}
echo 'End ...<br />';

By specifying the character set, the output is successfully transmitted to the client after each echo call, ensuring that the page is updated as logs are generated.

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