[Nero_3D]

you need to use a variable which marks the playerid as jailed

Example (one of the most known)

pawn Код:

new bool:IsLogged[MAX_PLAYERS]; //a variable marked with the boolean tag can only store false or true
//if nothing is assigned to the variable, it is 0 or false

pawn Код:

dcmd_login(playerid, password[])
{
    if("password is correct")
    {
        IsLogged[playerid] = true; //sets the variable to true
    }
}

pawn Код:

dcmd_help(playerid, unused[])
{
    #pragma unused unused
    if(IsLogged[playerid] == false) //if he isnt logged he gets a the message
        return SendClientMessage(playerid, 0xFFFFFFAA, "You arent logged!");
    SendClientMessage(playerid, 0xFFFFFFAA, "Help");
    return true;
}

This should be understandable

Offtopic
This section is for helping not for (so the person learns something)
Wuf, wuf, catch the code and be happy
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