How does INVALID_PLAYER_ID work?

How does INVALID_PLAYER_ID work? - Printable Version

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+--- Thread: How does INVALID_PLAYER_ID work? (/showthread.php?tid=226407)

How does INVALID_PLAYER_ID work? - !Phoenix! - 15.02.2011

Hey,

If you use "sscanf" you may use "INVALID_PLAYER_ID" to check if the player-id exists and someone is using it.
But how does it work? Any idea?

Re: How does INVALID_PLAYER_ID work? - Ash. - 15.02.2011

Erm, i know Y_Less is an amazing scripter, but i dont think the words INVALID_PLAYER_ID would mean he would want his script to check for if a player(id) EXISTS?

Then again, i havent read the documentation (which i probably should do) and there probably is an algorithm somewhere that causes it to do so.

Can i just ask, where did you read that INVALID_PLAYER_ID does what you said it does?

Re: How does INVALID_PLAYER_ID work? - The_Moddler - 15.02.2011

sscanf returns INVALID_PLAYER_ID if the player is invalid.

Re: How does INVALID_PLAYER_ID work? - Ash. - 15.02.2011

Quote:

Originally Posted by The_Moddler

sscanf returns INVALID_PLAYER_ID if the player is invalid.

I thought so. I cant quite see why it wouldnt, the word INVALID_PLAYER_ID are pretty self explantatory. Sorry if i caused confusion !Phoenix!

AW: How does INVALID_PLAYER_ID work? - !Phoenix! - 15.02.2011

Wiki:

pawn Code:

if (sscanf(params, "u", id)) SendClientMessage(playerid, 0xFF0000AA, "Usage: \"/heal <playerid>\"");
else if (id == INVALID_PLAYER_ID) SendClientMessage(playerid, 0xFF0000AA, "Player not found");

So if the id in sscanf(params, "u", id) is invalid " INVALID_PLAYER_ID" will be 0?
-> You can only use it with this special id?

Or does the retrieval of the " INVALID_PLAYER_ID" content runs something like a function?

Re: How does INVALID_PLAYER_ID work? - Ash. - 15.02.2011

INVALID_PLAYER_ID is equal to (0xFFFF)

(Source, a_samp.inc)

pawn Code:

#define INVALID_PLAYER_ID                       (0xFFFF)

AW: How does INVALID_PLAYER_ID work? - !Phoenix! - 15.02.2011

Re: How does INVALID_PLAYER_ID work? - Ash. - 15.02.2011

Sorry i should of explained better, i meant that INVALID_PLAYER_ID does not run a function or anything, it merely is (0xFFFF) and nothing more.

AW: How does INVALID_PLAYER_ID work? - !Phoenix! - 15.02.2011

I realized that but I don't understand how this can be used for an if-statement.
(You see I really want to understand how this unimposing comparison works)
Maybe the answer is unbelievable simple, but I don't get it...

(thanks funky)

Re: How does INVALID_PLAYER_ID work? - Mean - 15.02.2011

So.
Using it under OnPlayerDeath:

pawn Code:

if( killerid == INVALID_PLAYER_ID ) 
{
    SendClientMessage( playerid, 0xAAAAAA, "You have suicided, thefore you have no killer, no one killed you" );
}

Just an example.

Re: How does INVALID_PLAYER_ID work? - Calgon - 15.02.2011

sscanf checks if you use "u" and if it searches for a name or player ID with the "u" parameter and doesn't find anyone online with the information you provide, then it returns INVALID_PLAYER_ID instead of the players actual ID, you can compare the ID variable you assign with sscanf to INVALID_PLAYER_ID if the player isn't connected.

pawn Code:

new id; // Variable. The user ID from sscanf needs to be stored in this. If the player isn't connected, INVALID_PLAYER_ID is put as the variable value. 
if(sscanf(params, "u", id)) { 
// They didn't even provide anything after the command name. 
}
else {
// They provided something after the command name, our name. Are they connected?
if(id == INVALID_PLAYER_ID) {
// If this gets called, then the player isn't connected.
return 1;
}
}

AW: How does INVALID_PLAYER_ID work? - !Phoenix! - 15.02.2011

So INVALID_PLAYER_ID simply stands for "The playerid is overall not valid"?
Wouldn't that mean that if it's valid you still have to check if the player is connected?

//-------------
Calgon answered my question while I was writing this reply.

Re: How does INVALID_PLAYER_ID work? - Calgon - 15.02.2011

INVALID_PLAYER_ID does mean that an invalid player ID was specified, well that's what sscanf sets as the playerid if it can't find valid search criteria.

If INVALID_PLAYER_ID is returned then you don't need any more checks if you use sscanf to parse the userid/name - they aren't connected at all.

AW: How does INVALID_PLAYER_ID work? - !Phoenix! - 15.02.2011

That makes sense; thank you!

(see my last post)

Re: How does INVALID_PLAYER_ID work? - Mean - 15.02.2011

Also, you can use !IsPlayerConnected:

pawn Code:

if( !IsPlayerConnected( playerid ) ) 
 // If this gets called, player is not on the server

Re: How does INVALID_PLAYER_ID work? - vldmrtal - 06.01.2012

How can i use INVALID_PLAYER_ID ?
TO ALL ID at the TAB BAR?
sry I ONLY SCRIPT LITTLE.