fflush

(PHP 4 >= 4.0.1, PHP 5)

fflush — Zapíše obsah výstupního bufferu

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bool fflush ( resource $handle )

Funkce vynutí okamžitý zápis veškerých dat uložených ve výstupním bufferu do souboru odkazovaného pomocí deskriptoru fp. Vrací TRUE při úspěchu, jinak FALSE.

Deskriptor souboru musí být platný a musí ukazovat na soubor úspěšně otevřený pomocí fopen(), popen(), nebo fsockopen().

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fflush

oryan at zareste dot com
30-Oct-2005 04:48


Just a note that fflush takes care of the cache already, at least on my server.  Using clearstatcache before reading a previously written file also worked, but lagged the output time much more noticeably (by two or three seconds), probably due to excess cache erasing beyond files.

jzho327 at cse dot unsw dot edu dot au
27-Jan-2003 12:27


Sorry, the note I previously added regarding fflush() has a bug!



when you read file by calling 

$fp = fopen("myfile", "a+");



and you wish to read the content, you have to call 

rewind($fp) before you attemp to read it. (Silly me) Or else if you tried something like

$fp = fopen("myfile", "a+");

$content = fread($fp);



// show that content is in fact null

if ($content == NULL)

 print "but it must be first put to rewind<br>\n";



will result



but it must be first put to rewind.

[new line]



in fact, if you are not careful (like me), and you opened it with

$fp = fopen("myfile", "r+");

$content = fread($fp);

..

// do something with content

..

then you tried to again

$content = fread($fp);

without rewind, you'd get NULL again. This sounds trivial, but if you work with several file resources, with freads and fopens everywhere, you can get easily lost. So becareful.

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fgetc

feof

Last updated: Sat, 24 Mar 2007