SHELL (function)

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The SHELL function displays the console and returns the INTEGER code value sent when the external program exits.


Syntax

return_code = SHELL(DOScommand$)


Parameters

  • The literal or variable STRING command parameter can be any valid external command or call to another program.


Usage:

  • A SHELL to a QB64 EXE program with an exit return code parameter after END or SYSTEM will return that code value.
  • The return_code is usually 0 when the external program ends with no errors.
  • The console window may appear when using the SHELL function. The _SHELLHIDE function will hide the console from view.


Example: Shelling to another QB64 program will return the exit code when one is set in the program that is run.

'DesktopSize.BAS Compile in Windows with QB64 first CONST SM_CXSCREEN = 0 CONST SM_CYSCREEN = 1 DECLARE LIBRARY FUNCTION GetSystemMetrics& (BYVAL n AS LONG) END DECLARE PRINT trimstr$(GetSystemMetrics(SM_CXSCREEN)); "X"; trimstr$(GetSystemMetrics(SM_CYSCREEN)) s& = _SCREENIMAGE PRINT _WIDTH(s&); "X"; _HEIGHT(s&) END 3 '<<<<<< add a code to return after END or SYSTEM in any program FUNCTION trimstr$ (whatever) trimstr = LTRIM$(RTRIM$(STR$(whatever))) END FUNCTION

Explanation: To set a program exit code use an INTEGER parameter value after END or SYSTEM in the called program.
After compiling DesktopSize.EXE run the following code in the QB64 IDE. After 1st program is done 3 will appear on screen:

returncode% = SHELL("DesktopSize") 'replace call with name of any QB64 program EXE PRINT returncode% 'prints code sent by called program after it is closed END

3


See also:



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