I occasionally need to call out to a batch file or an executable in my
Lotusscript. The problem is the code has no native way of knowing when
the external process has completed. Hence Execute and wait.
Using the windows API you can create a process and wait for it to
complete in you lotusscript code before continuing.
an example would be where you need to run a command-line tool, with
arguments, from your code. The output is a csv file that you then need
to import. The size of the data is not guaranteed so you need to wait
for the windows process to complete before importing.
Example code below
'this is the win32 api information
Const NORMAL_PRIORITY_CLASS = &H20&
Const INFINITE = -1&
Type STARTUPINFO
cb As Long
lpReserved As String
lpDesktop As String
lpTitle As String
dwX As Long
dwY As Long
dwXSize As Long
dwYSize As Long
dwXCountChars As Long
dwYCountChars As Long
dwFillAttribute As Long
dwFlags As Long
wShowWindow As Integer
cbReserved2 As Integer
lpReserved2 As Long
hStdInput As Long
hStdOutput As Long
hStdError As Long
End Type
Const STARTF_USESHOWWINDOW = &H1
Const SW_MINIMIZE = 6
Type PROCESS_INFORMATION
hProcess As Long
hThread As Long
dwProcessID As Long
dwThreadID As Long
End Type
Declare Function CloseHandle Lib "kernel32" (hObject As Long) As Boolean
Declare Function WaitForSingleObject Lib "kernel32" (ByVal hHandle As
Long,ByVal dwMilliseconds As Long) As Long
Declare Function CreateProcessA Lib "kernel32" (ByVal lpApplicationName
As Long,ByVal lpCommandLine As String, ByVal lpProcessAttributes As
Long, ByVallpThreadAttributes As Long, ByVal bInheritHandles As Long,
ByVal dwCreationFlags As Long, ByVal lpEnvironment As Long, ByVal
lpCurrentDirectory As Long, lpStartupInfo As
STARTUPINFO,lpProcessInformation As PROCESS_INFORMATION) As Long
Sub Initialize()
Dim cmdline As String ' this it the command you wish to run
cmdline = "application.exe -r -p -l output.csv"
Call ExecuteAndWait(cmdline)
msgbox "process finished"
end sub
' this creates the windows process and waits for it to finish before
continuing on
Sub ExecuteAndWait(cmdline)
Dim NameOfProc As PROCESS_INFORMATION
Dim NameStart As STARTUPINFO
Dim X As Long
NameStart.wShowWindow = SW_MINIMIZE
NameStart.dwFlags = STARTF_USESHOWWINDOW
NameStart.cb = Len(NameStart)
X = CreateProcessA(0&, cmdline, 0&, 0&, 1&,
NORMAL_PRIORITY_CLASS,0&, 0&, NameStart, NameOfProc)
X = WaitForSingleObject(NameOfProc.hProcess, INFINITE)
X = CloseHandle(NameOfProc.hProcess)
End Sub
There you have it pretty simple and straightforward