Special Thanks to Diez B. Roggisch and Eric Brunel. Last week on Friday I solved the problems I encountered thanks to your helpful indications.
I think I covered all the ambiguity in my code. Here's the code: # executing CCCC with Python from Tkinter import * from tkFileDialog import * import tkMessageBox import os # Creating App Class class App: b_file = "" # Function to browse files, the files selected will be the items of a tuple # This tuple is assigned to the instance of App class # browseFile Function is triggered by a label in Menu def browseFile(self): App.b_file App.b_file = askopenfilename(filetypes = [("C Source Code", "*.c"), ("C Header Files", "*.h"), ("All Files", "*.*")], multiple=1) # Function to Run CCCC Code Analyzer def runCCCC(self, event): # Controls if a file is browsed and selected # If a selection is done the code continues from here if App.b_file != "": cmd_tup = "" for i in range(len(App.b_file)): cmd_tup += App.b_file[i]+' ' # The type of the a tuple's items are all strings, here parameter for CCCC are arranged cmd = 'cccc ' + cmd_tup #according to the #command prompt syntax, command is created return os.system(cmd) # command is executed else: tkMessageBox.showinfo("Window Text", "Please Firstly Browse and Select A File") # if no file is selected a warning pop-ups def __init__(self, master): frame = Frame(master) frame.pack(fill="both") self.menubar = Menu(master) self.menubar.add_command(label="Browse File", command=self.browseFile) master.config(menu=self.menubar) self.ccccRun = Button(frame, text="Run CCCC", fg="red") self.ccccRun.bind("<Button-1>", self.runCCCC) self.ccccRun.pack(side=LEFT, padx=10, pady=20) self.close = Button(frame, text="QUIT", fg="red", command=frame.quit) self.close.pack(side=LEFT, padx=10, pady=20) root = Tk() app=App(root) root.mainloop() __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com -- http://mail.python.org/mailman/listinfo/python-list