execShell VBA module by Robert Knight

execShell.bas

' This User Defined Function was written by Robert Knight of StackOverflow
' Designed for Excel 2011, though it might work in the Windoze version too.
' It is shared here for posterity.
 
 
Private Declare Function popen Lib "libc.dylib" (ByVal command As String, ByVal mode As String) As Long
Private Declare Function pclose Lib "libc.dylib" (ByVal file As Long) As Long
Private Declare Function fread Lib "libc.dylib" (ByVal outStr As String, ByVal size As Long, ByVal items As Long, ByVal stream As Long) As Long
Private Declare Function feof Lib "libc.dylib" (ByVal file As Long) As Long
 
Function execShell(command As String, Optional ByRef exitCode As Long) As String
    Dim file As Long
    file = popen(command, "r")
 
    If file = 0 Then
        Exit Function
    End If
 
    While feof(file) = 0
        Dim chunk As String
        Dim read As Long
        chunk = Space(50)
        read = fread(chunk, 1, Len(chunk) - 1, file)
        If read > 0 Then
            chunk = Left$(chunk, read)
            execShell = execShell & chunk
        End If
    Wend
 
    exitCode = pclose(file)
End Function
 
Sub RunTest()
    Dim result As String
    Dim exitCode As Long
    result = execShell("echo Hello World", exitCode)
    Debug.Print "Result: """ & result & """"
    Debug.Print "Exit Code: " & str(exitCode)
End Sub