check for empty pointer

Gamestudio Links

Zorro Links

loading historical data 1st time
by AndrewAMD. 04/14/23 12:54

Trade at bar open
by juanex. 04/13/23 19:43

Bug in Highpass2 filter
by rki. 04/13/23 09:54

Adding Limit Orders For IB
by scatters. 04/11/23 16:16

FisherN
by rki. 04/11/23 08:38

AUM Magazine

Latest Screens

3 registered members (AndrewAMD, Grant, Neb), 908 guests, and 6 spiders.

Key: Admin, Global Mod, Mod

Newest Members

Print Thread

Rate Thread

Page 1 of 2

check for empty pointer #400787 05/07/12 20:00 05/07/12 20:00
Joined: Apr 2008 Posts: 245 GameScore OP Member
GameScore OP Member Joined: Apr 2008 Posts: 245	can someone tell me please how can i check a pointer is empty or not?

Re: check for empty pointer [Re: GameScore] #400789 05/07/12 20:27 05/07/12 20:27
Joined: Jul 2001 Posts: 6,904 H HeelX Senior Expert
HeelX Senior Expert H Joined: Jul 2001 Posts: 6,904	You can check it against NULL. Like Code: ENTITY* ent = ent_create(...); if (ent != NULL) { // do something }

Re: check for empty pointer [Re: HeelX] #400790 05/07/12 20:39 05/07/12 20:39
Joined: Apr 2008 Posts: 245 GameScore OP Member
GameScore OP Member Joined: Apr 2008 Posts: 245	tnx for your answer i was try with the same like your example but i got a scripcrash Code: ENTITY* ent = ent_create(...); if (ent != NULL) { ent_remove(ent); } else { return; }

Re: check for empty pointer [Re: GameScore] #400791 05/07/12 20:48 05/07/12 20:48
Joined: Jul 2001 Posts: 6,904 H HeelX Senior Expert
HeelX Senior Expert H Joined: Jul 2001 Posts: 6,904	Hm I cannot say something fruitful about that, because you would have to post the surrounding function for that. Maybe the error arises from somewhere else?

Re: check for empty pointer [Re: HeelX] #400800 05/08/12 06:56 05/08/12 06:56
Joined: Nov 2011 Posts: 274 de lemming Member
lemming Member Joined: Nov 2011 Posts: 274 de	If you remove the object but don't set the pointer to NULL, comparison against NULL won't work. Always use safe_remove(ent) instead ptr_remove(ent). This will delete the object AND set ent* to NULL.

Re: check for empty pointer [Re: lemming] #400803 05/08/12 07:55 05/08/12 07:55
Joined: Apr 2008 Posts: 245 GameScore OP Member
GameScore OP Member Joined: Apr 2008 Posts: 245	sounds great but i dont find something about safe_remove(ent) in the manual i will test it when i`m at home tonight tnx Last edited by GameScore; 05/08/12 07:55.

Re: check for empty pointer [Re: GameScore] #400809 05/08/12 08:50 05/08/12 08:50
Joined: Nov 2011 Posts: 274 de lemming Member
lemming Member Joined: Nov 2011 Posts: 274 de	It's a define in acknex.h. #define safe_remove(ptr) if(ptr) ptr = ptr_remove(ptr) I can't remember where I got it from, as it really isn't in the manual.

Re: check for empty pointer [Re: lemming] #400921 05/09/12 19:17 05/09/12 19:17
Joined: Apr 2008 Posts: 245 GameScore OP Member
GameScore OP Member Joined: Apr 2008 Posts: 245	wow! i test it and works perfect! this is really god to know TNX!

Re: check for empty pointer [Re: GameScore] #401057 05/12/12 14:26 05/12/12 14:26
Joined: Dec 2009 Posts: 128 China frankjiang Member
frankjiang Member Joined: Dec 2009 Posts: 128 China	if(ent!=NULL) printf("%",ent); else return; development 3d game is interesting!

Re: check for empty pointer [Re: frankjiang] #401647 05/22/12 21:35 05/22/12 21:35
Joined: Jan 2010 Posts: 150 iran - tehran F flatron Member
flatron Member F Joined: Jan 2010 Posts: 150 iran - tehran	when i change level, i have a same problem. some entities removed but thair pointer is not null so if i use ent_purge, a script crash happed what about this

Page 1 of 2