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Private Declare Function CreatePipe Lib "kernel32" (phReadPipe As Long, phWritePipe As Long, lpPipeAttributes As Any, ByVal nSize As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
Private Declare Function CreateProcess Lib "kernel32" Alias "CreateProcessA" (ByVal lpApplicationName As String, ByVal lpCommandLine As String, lpProcessAttributes As Any, lpThreadAttributes As Any, ByVal bInheritHandles As Long, ByVal dwCreationFlags As Long, lpEnvironment As Any, ByVal lpCurrentDriectory As String, lpStartupInfo As STARTUPINFO, lpProcessInformation As PROCESS_INFORMATION) As Long
'Private Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, lpOverlapped As OVERLAPPED) As Long
Private Declare Function ReadFile Lib "kernel32" (ByVal hFile As Long, lpBuffer As Any, ByVal nNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long, ByVal lpOverlapped As Long) As Long
Private Declare Function WaitForSingleObject Lib "kernel32" (ByVal HHandle As Long, ByVal dwMilliseconds As Long) As Long
Private Type SECURITY_ATTRIBUTES
nLength As Long
lpSecurityDescriptor As Long
bInheritHandle As Long
End Type
Private 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
Private Type PROCESS_INFORMATION
hProcess As Long
hThread As Long
dwProcessID As Long
dwThreadId As Long
End Type
Private Const NORMAL_PRIORITY_CLASS = &H20
Private Const INFINITE = &HFFFF
Private Const STARTF_USESHOWWINDOW = &H1
Private Const STARTF_USESTDHANDLES = &H100
Private Const SW_HIDE = 0
Function ShellToVariable(ByVal cmdLine As String, ByRef Output As String) As Long
Dim ReadPipe As Long
Dim WritePipe As Long
Dim SA As SECURITY_ATTRIBUTES
Dim SI As STARTUPINFO
Dim PI As PROCESS_INFORMATION
Dim Data() As Byte
Dim Length As Long
'Set up the Security Attributes
SA.nLength = Len(SA)
SA.lpSecurityDescriptor = 0
SA.bInheritHandle = 1
'Create the pipe
If CreatePipe(ReadPipe, WritePipe, SA, 0) = 0 Then
Exit Function
End If
'Set up the window state and STDIO handles
SI.cb = Len(SI)
SI.dwFlags = STARTF_USESTDHANDLES Or STARTF_USESHOWWINDOW
SI.wShowWindow = SW_HIDE
SI.hStdInput = 0
SI.hStdOutput = WritePipe
SI.hStdError = WritePipe
'Try and run the process
If CreateProcess(vbNullString, cmdLine, SA, SA, 1, NORMAL_PRIORITY_CLASS, vbNullString, vbNullString, SI, PI) = 0 Then
Exit Function
End If
'Wait for the process to exit
WaitForSingleObject PI.hProcess, INFINITE
'Close both handles so it can shut down correctly
CloseHandle PI.hProcess
CloseHandle PI.hThread
'Attempt to read the data (1K is enough for now)
Length = 1024
ReDim Data(Length - 1)
If ReadFile(ReadPipe, Data(0), Length, Length, 0) = 0 Then
Data = ""
Else
ReDim Preserve Data(Length - 1)
End If
Output = StrConv(Data, vbUnicode)
'Close the pipe handles
CloseHandle ReadPipe
CloseHandle WritePipe
End Function
