After a 2-second search of the PHP manual... "require() and include() are identical in every way except how they handle failure. include() produces a Warning while require() results in a Fatal Error. In other words, don't hesitate to use require() if you want a missing file to halt processing of the page. include() does not behave this way, the script will continue regardless. Be sure to have an appropriate include_path setting as well." And.. "The include_once() statement includes and evaluates the specified file during the execution of the script. This is a behavior similar to the include() statement, with the only difference being that if the code from a file has already been included, it will not be included again. As the name suggests, it will be included just once." > -----Original Message----- > From: Mikhail U. Petrov [mailto:mikhail@xxxxxxxx] > Sent: Tuesday, April 13, 2004 2:07 PM > To: Eric Girard > Cc: Karen Resplendo; php-db@xxxxxxxxxxxxx > Subject: Re[2]: Curious if include_once will work better than > include > > > Hi! > Sorry for my offtopic, but by the way, > what's the difference between include/include_once and > require/require_once? > > > Tuesday, April 13, 2004, 10:29:14 PM, Eric wrote: > > >> Curious about "include_once" versus "include". > >> > >> All my connection stuff is in "conn.php3". > >> > >> I am planning on including it at the top of the page like this: > >> include_once "conn.php3"; > >> > >> Now will that speed things up compared to just using a > plain "include". I > >> call $connectionSDWIS(which is in the include) 5 different times? > > EG> IMHO the 'speed' difference between include and > include_once will be > EG> slight, probably with include_once being slower because > of the overhead > EG> needed to keep track of which files have been included > already. But this > EG> isn't really what the question is about. include and > include_once will > EG> not magically optimize the code for you, but if you > include the same file > EG> 20 times that will be more that has to be parsed > needlessly, so if you > EG> can't keep track of your includes or if including a > particular file more > EG> than once will alter the result, than use include_once. Another > EG> alternative is to use require() or require_once() to make > sure that the > EG> file is included. Just my $.02, > > EG> Eric > > > > -- > Best regards, > Mikhail U. Petrov > mailto:mikhail@xxxxxxxx > > -- > PHP Database Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > > -- PHP Database Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
