Re: Question about session_id() and session_start()

thank you. I read the source code and it helps a lot, now I know the behavior of the code is consistent with the NOTE. I think the reason is that If the 'new' session_id we want to set already exists on the server, but does not exist on the client's cookie, the server must send a set-cookie header to the client. On Tue, May 21, 2013 at 3:50 PM, Tim Schofield <tim@weberpafrica.com> wrote: > On 20/05/2013, Maciek Sokolewicz <maciek.sokolewicz@gmail.com> wrote: > > On 20-5-2013 22:14, Tim Schofield wrote: > >> Matijn > >> > >> There are well over half a million lines of source code in PHP. It seems > >> a > >> little unhelpful to tell someone to go and read half a million lines of > C > >> when you could just tell them the answer? > >> > >> Thanks > >> Tim > >> > >> Course View Towers, > >> Plot 21 Yusuf Lule Road, > >> Kampala > >> T +256 (0) 312 314 418 > >> M +256 (0) 752 963 325 > >> www.weberpafrica.com > >> Twitter: @TimSchofield2 > >> Blog: http://weberpafrica.blogspot.co.uk > >> On May 20, 2013 6:24 PM, "Matijn Woudt" <tijnema@gmail.com> wrote: > >> > >>> On Mon, May 20, 2013 at 5:33 AM, 孟远涛 <yuantao..meng@gmail.com> wrote: > >>> > >>>> I find the Note in PHP document. > >>>> > >>>> http://www.php.net/manual/en/function.session-id.php > >>>> > >>>> "Note: When using session cookies, specifying an id for session_id() > >>>> will > >>>> always send a new cookie when session_start() is called, regardless if > >>> the > >>>> current session id is identical to the one being set." > >>>> > >>>> I feel puzzled about this feature. Even if the current session id is > >>>> identical to the one one being set, session_start will send a new > >>> cookie. I > >>>> want to know why session_start behave in this way. > >>>> > >>>> Forgive my poor English. Thanks in advance. > >>>> > >>> > >>> You will find the answer in the PHP source code. > >>> If you don't want this to happen, check if the current session id > >>> matches > >>> with the value you want to set it to, and don't set if they match. > >>> > >>> - Matijn > >>> > >> > > > > Tim, > > > > first of all, please bottom-post on this list. > > Tell that to the designers of the android gmail app :-) > > > Secondly, a simple google search for "php c session_start" resulted in > > this: > > > > https://github.com/php/php-src/blob/master/ext/session/session.c#L1303 > > That wasn't the advice given. The advice given was to read the source > code. My point was that is not very helpful advice. With a few notable > exceptions the help given on this list has become less and less > friendly over the years I have been reading it. This can't be good for > the PHP community. > > > > > - Tul > > > > > > Tim > > -- > Course View Towers, > Plot 21 Yusuf Lule Road, > Kampala > T +256 (0) 312 314 418 > M +256 (0) 752 963 325 > www.weberpafrica.com > @TimSchofield2 > Blog: http://weberpafrica.blogspot.co.uk/ > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > >