PHP function progress bar

i'm building some image convertor and the function i run may can take a while , what i want to know , is if there a build in way in php that i can use to show the progress of the function? the function based on the For loop (inside the function there are several for loop ) so i know in many loops the开发者_开发技巧 function going to stop. is it possible?

an other question is that i want to know how uploading files progress bar work , if you have small example or tutorial it will be great , thanks , Mor.

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Yes it is possible, to use flush() and ob_flush() to flush output buffering while executing script

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Check thie out http://pixomania.net/dev/php/php-progress-bar-class