Output Control 函数
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ob_implicit_flush

(PHP 4, PHP 5)

ob_implicit_flush — 打开/关闭绝对刷送

说明

void ob_implicit_flush ([ int $flag = true ] )

ob_implicit_flush()将打开或关闭绝对（隐式）刷送。绝对（隐式）刷送将导致在每次输出调用后有一次刷送操作，以便不再需要对 flush() 的显式调用。

参数

flag

设为TRUE 打开绝对刷送，反之是 FALSE 。

返回值

没有返回值。

参见

Output Control 函数
在线手册：中文 英文
PHP手册
PHP手册 - N: 打开/关闭绝对刷送

用户评论:

rocca at start dot ca (09-Oct-2007 07:42)

You can also get the unbuffered output with Linux/Apache without having to do the implicit flush after each line by calling:

ob_implicit_flush(true);
ob_end_flush();

...at the start of the script.

Paul Yanchenko (22-Jan-2006 12:15)

There is another workaround for ob_implicit_flush() in console. Yes, it doesn't works as expected, but you can get similar result by specifying chunk_size=2 in ob_start():

<?php
  ob_start('ob_logstdout', 2);
?>

This will result that every new line (which ends with \n) will flush output buffer.

Hope this will help you.

mhumphrey at _spammenot_designvision dot com (18-Aug-2003 10:41)

From experimenting, it looks like using sessions with session.use_trans_sid=1 will force your output to be buffered regardless of this setting.

My guess is that this is so PHP can hunt for URLs in your output to automatically add the Session ID to them.  It must wait until script output is complete before it starts that replacement, rather than doing it "on the fly".

When i comment out my session_start() line, i get continuous output to the browser.  Put it back in, and i only see the page when it's completely loaded.  Change session.use_trans_sid = 0 and i get continuous output again.

calimero at Creatixnet dot com (07-Jul-2003 08:00)

######### BEWARE ##########

There is a bug (or at least an unexpected feature of ob_implicit_flush) that has been already discussed on the PHP bugtracker :

http://bugs.php.net/bug.php?id=23877
http://bugs.php.net/bug.php?id=16676

Code like this WILL NOT work :

<?
// This will not work as expected on Linux.
ob_implicit_flush (1);
for($i=0;$i<10;$i++) {
   echo "grrrrrrrrrr\n";
   sleep(1);
}
?>

This feature happens on Linux versions of PHP, in all versions of php4 prior to 4.3.3 (don't know yet for the next ones) but also in php5 beta1. ob_implicit_flush has NO EFFECT on command-line (console, CLI) scripts, no flushing at all will be made, all output will be sent at the end of the script.

There is a workaround using ob_end_flush() and ob_flush, here it is :

<?
// This works !
ob_end_flush();
for($i=0;$i<10;$i++) {
  echo "yeah :-))))\n";
  @ob_flush();
  sleep(1);
}
?>

hope this will help. It would have helped me...