Call a Unix Script from Excel Vba

One option would be to open the plink session in a WScript.Shell instead of executing it with a script file using VBA’s Shell. The plink program will run in interactive mode from the command line, and the WshExec object gives you direct access to the standard input and standard output streams of the process that you’re executing. This short example demonstrates using it interactively (it logs onto the public telehack.com telnet server and executes the fnord command) with all of the console output being copied into the immediate window:

Private Sub Fnord()
    Dim shell As Object
    Set shell = CreateObject("WScript.Shell")
    Dim console As Object
    'Open plink in interactive mode.
    Set console = shell.Exec("c:\putty\plink -telnet telehack.com -P 443")
    'Wait for a command prompt.
    WaitForResponseText console, "."
    'Send the fnord command to standard input.
    console.StdIn.Write ("fnord" & vbCr)
    'Wait for the server to echo it back.
    WaitForResponseText console, ".fnord"
    'Read the standard output through the next command prompt.
    WaitForResponseText console, "."
    'Exit the telent session.
    console.StdIn.Write ("exit" & vbCr)
End Sub

Private Sub WaitForResponseText(console As Object, response As String)
    Dim out As String
    'Make sure there's output to read.
    If console.StdOut.AtEndOfStream Then Exit Sub
    Do
        'Read a line from standard output.
        out = console.StdOut.ReadLine()
        'Not strictly required, but allows killing the process if this doesn't exit.
        DoEvents
        'Send the server output to the immediate window.
        Debug.Print out
        'Check for the response we're waiting for.
        If InStr(out, response) Then
            Exit Do
        End If
    Loop Until console.StdOut.AtEndOfStream
End Sub

In your case, there isn’t much “interaction” going on with the server you’re connecting to, so it may be as easy as just sending all of your commands directly to StdIn. Given the wide range of protocol support that plink has, I’d be surprised if running the script file is substantially different that this:

Public Sub Chgaccper()
    Dim shell As Object
    Set shell = CreateObject("WScript.Shell")
    Dim console As Object
    'Open plink in interactive mode.
    Set console = shell.Exec("c:\putty\plink server Name -l uname -pw Password")
    'Send your commands to the standard input.
    console.StdIn.Write ("cd /root/home/temp" & vbCr)
    console.StdIn.Write ("chmod 666 *.csv" & vbCr)
    console.StdIn.Write ("cd /root/home/temp1" & vbCr)
    console.StdIn.Write ("chmod 666 *.csv" & vbCr)
    console.StdIn.Write ("exit" & vbCr)
End Sub

If that runs too fast, you can always test to make sure you’re getting appropriate server responses or add a short wait between sending commands to StdIn.

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