canView, canDeposit, stacksPerDay = GetGuildBankTabPermissions(tab);

Parameters Edit

Arguments Edit

tab 

Integer - guild bank tab number

Returns Edit

canView 

Boolean - 1 if the selected rank can view this guild bank tab, nil otherwise.

canDeposit 

Boolean - 1 if the selected rank can deposit to this guild bank tab, nil otherwise.

stacksPerDay 

Integer - Amount of withdrawable stacks per day or 0 if none.

Example Edit

local canView, canDeposit, stacksPerDay = GetGuildBankTabPermissions(1);
if canDeposit then
 DEFAULT_CHAT_FRAME:AddMessage("Can view, deposit and retrieve " .. stacksPerDay .. " stacks a day on tab 1.");
elseif canView then
 DEFAULT_CHAT_FRAME:AddMessage("Can view and retrieve " .. stacksPerDay .. " stacks a day on tab 1.");
else
 DEFAULT_CHAT_FRAME:AddMessage("Can not view tab 1.");
end

Result Edit

If you are the guild master, this will return data for the rank you currently have selected in guild control. Else, it will return data for your own rank.

Guild masters can always view, deposit and withdraw without limits; this function does not properly return that. Use IsGuildLeader(UnitName("player")) if you want to know if this is the case.

Note that being able to deposit implies being able to view.