static gPlayerViewingList[playerid] = {0, ...};

public OnPlayerText(playerid, const text[])
{
	new str[48];
	GetPlayerName(playerid, str, sizeof (str));
	format(str, sizeof (str), "%s: %s", str, text);
	for (new i = 0; i < MAX_PLAYERS; i++)
	{
		if (IsPlayerConnected(i) && !gPlayerViewingList[i])
		{
			SendClientMessage(i, 0xFF0000FF, str);
		}
	}
	return 0;
}

OnPlayerCommandText(playerid, const cmdtext[])
{
	if (strcmp(cmdtext, "/list", true) == 0 || strcmp(cmdtext, "/more", true) == 0)
	{
		// Read and display 9 lines here starting at line gPlayerViewingList[playerid]
		if (gPlayerViewingList[playerid] < max number of lines - 9)
		{
			gPlayerViewingList[playerid] += 9;
			SendClientMessage(playerid, 0x00FFFFFF, "Type /more for more");
		}
		else
		{
			gPlayerViewingList[playerid] = 0;
		}
		return 1;
	}
	return 0;
}