MQL4 Help as One File:

State Checking

Functions that return parameters of the current state of the client terminal

Function	Action
GetLastError	Returns the last error
IsStopped	Returns true, if an mql4 program has been commanded to stop its operation
UninitializeReason	Returns the code of the reason for deinitialization
MQLInfoInteger	Returns an integer value of a corresponding property of a running mql4 program
MQLInfoString	Returns a string value of a corresponding property of a running mql4 program
MQLSetInteger	Sets the value of the MQL_CODEPAGE property in an MQL4 program environment
TerminalInfoInteger	Returns an integer value of a corresponding property of a running mql4 program
TerminalInfoDouble	Returns a double value of a corresponding property of a running mql4 program
TerminalInfoString	Returns a string value of a corresponding property of a running mql4 program
Symbol	Returns the name of a symbol of the current chart
Period	Returns the current chart timeframe
Digits	Returns the number of decimal digits determining the accuracy of the price value of the current chart symbol
Point	Returns the point size of the current symbol in the quote currency
IsConnected	Checks connection between client terminal and server
IsDemo	Checks if the Expert Advisor runs on a demo account
IsDllsAllowed	Checks if the DLL function call is allowed for the Expert Advisor
IsExpertEnabled	Checks if Expert Advisors are enabled for running
IsLibrariesAllowed	Checks if the Expert Advisor can call library function
IsOptimization	Checks if Expert Advisor runs in the Strategy Tester optimization mode
IsTesting	Checks if the Expert Advisor runs in the testing mode
IsTradeAllowed	Checks if the Expert Advisor is allowed to trade and trading context is not busy
IsTradeContextBusy	Returns the information about trade context
IsVisualMode	Checks if the Expert Advisor is tested in visual mode
TerminalCompany	Returns the name of company owning the client terminal
TerminalName	Returns client terminal name
TerminalPath	Returns the directory, from which the client terminal was launched

AccountStopoutModeGetLastError