Iterate through the folder and find a particular file - vbscript

Question

I have written this code to iterate through the folders and exit the function when it finds the ".c" file. Ideally it should return the path of the ".c" file. But its returning empty string.
tval = 1
Function findStlcode(objFSO,fFolder,folderName)
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set Folder = objFSO.GetFolder(fFolder)
Set colfiles = Folder.Files
For Each objFile In colfiles
strFilename = objFile.name
If strcomp(strFilename,folderName & ".c",vbTextCompare) = 0 Then
findStlcode = fFolder & "\" & folderName & ".c"
tval = tval + 1
Exit Function
End If
Next
For Each Subfolder In Folder.SubFolders
If tval = 1 Then
xx = findStlcode(objFSO, Subfolder.Path, folderName)
End If
Next
End Function

Answer 1

Change the FOR loop contents to below, change xx to findStlcode and it should work
strFilename = objFile.name
If Right(strFilename, 2) = ".c" Then
findStlcode = fFolder & "\" & strFilename
tval = tval + 1
Exit Function
End If
Complete code below
tval = 1
Function findStlcode(objFSO,fFolder)
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set Folder = objFSO.GetFolder(fFolder)
Set colfiles = Folder.Files
For Each objFile In colfiles
strFilename = objFile.name
If Right(strFilename, 2) = ".c" Then
findStlcode = fFolder & "\" & strFilename
tval = tval + 1
Exit Function
End If
Next
For Each Subfolder In Folder.SubFolders
If tval = 1 Then
findStlcode = findStlcode(objFSO, Subfolder.Path)
End If
Next
End Function
Calling the Function
Set objFSO = CreateObject("Scripting.FileSystemObject")
Wscript.Echo findStlcode(objFSO, "C:\")

Answer 2

The root cause of your problem is that your function doesn't actually return the path (by assigning it to the function name), as others have already pointed out.
There are, however, some other issues with your implementation that you may want to address:
You shouldn't use a global variable to keep track of whether a matching file was found or not. The return value of the recursive function calls can be used to the same effect.
There's no point in passing objFSO if you're going to re-create it with each function call anyway. In practically every case it's better to create a FileSystemObject instance as a global (singleton) object and use that everywhere in your script.
Pass folder objects instead of path strings, so you don't have to turn the string back into a folder object in the next recursion step.
If you're going to check for an extension, use the appropriate method to extract the extension from a file name (GetExtensionName).
Something like this would suffice:
Set fso = CreateObject("Scripting.FileSystemObject")
Function findStlcode(fldr)
Dim f, sf, path
For Each f In fldr.Files
If LCase(fso.GetExtensionName(f)) = "c" Then
path = f.Path
Exit For
End If
Next
For Each sf In fldr.SubFolders
If IsEmpty(path) Then path = findStlcode(sf)
Next
findStlcode = path
End Function
startFolder = "C:\some\folder"
cfile = findStlCode(fso.GetFolder(startFolder))