Something

public OnPlayerDisconnect(playerid)
{
	new File:stats = fopen("stats.txt", io_append);
	new pname[MAX_PLAYER_NAME];
	new str[256], str2[256];
	GetPlayerName(playerid, pname, 256);
	while(fread(stats, str)) {
	    if(strcmp(str, pname, true, strlen(pname))==0) {
	        strdel(str, 1, strlen(str));
		 	format(str2, sizeof(str2), "\n%s %d %d\n", pname, gPlayerDeaths[playerid], gPlayerKills[playerid]);
		  	fwrite(stats, str2);
		}
	}
	fclose(stats);
   	return 1;
}