if split == True:
                fout_split = []
                for i in range(split_size):
                    fout_split[i] = open("clink.part" + str(i+1), 'w')

            n = 0
            feature_vectors = ""
            for r, d, f in os.walk(dirpath):
                for filename in f:
                    #print filename
                    #sys.stderr.write(filename + "\n")
                    if filename.endswith(".txp"):
                        filepath = os.path.join(r, filename)
                        input_file = open(filepath, 'r')
                        file_features = ff.FileFeatures(input_file.read(), filename, language, parser, inverse)
                        file_features.getFeatures()
                        if dirpath_csignal != "":
                            filepath_csignal = os.path.join(dirpath_csignal, filename+".csignals")
                            file_csignal = open(filepath_csignal, "r")
                            file_features.initCSignals(file_csignal.read())
                            file_csignal.close()
                        if dirpath_tlink != "":
                            filepath_tlink = os.path.join(dirpath_tlink, filename+".tlinks")
                            file_tlink = open(filepath_tlink, "r")
                            file_features.initTlinkPairs(file_tlink.read())
                            file_tlink.close()
                        if dirpath_clink != "":
                            filepath_clink = os.path.join(dirpath_clink, filename+".clinks")
                            file_clink = open(filepath_clink, "r")
                            file_features.initPairs(file_clink.read())