import os, sys, traceback, arcgisscripting
gp = arcgisscripting.create()

try:
    def unique_name(filename, part):
        base, ext = filename.split('.')
        return base + str(part) + '.' + ext        
    #input_file = 'c:\carlin_gis\combine_kbge1_class0.dta'
    input_file = gp.GetParameterAsText(0)
    split_len = 200000
    fdin = open(input_file, 'r')
    save1 = fdin.readline()
    save2 = fdin.readline()
    save3 = fdin.readline()
    num_data = int(fdin.readline()[:-1])
    if num_data < split_len:
        raise Exception('not enough data to partition')
    else:
        num_whole_parts = num_data // split_len
        len_last_part = num_data % split_len
        len_parts = [split_len for i in range(num_whole_parts)] + [len_last_part]
        for part_n, part_len in enumerate(len_parts):
            fdout = open(unique_name(input_file, part_n+1), 'w')
            print 'processing partition %s...'%(fdout.name)
            gp.addmessage('processing partition %s...'%(fdout.name))
            fdout.write(save1)
            fdout.write(save2)
            fdout.write(save3)
            fdout.write(str(part_len) + '\n')
            for n, line in enumerate(fdin):
                fdout.write(line)
                if n > 1 and n % split_len == (split_len-1): break
            fdout.close()
    fdin.close()
except Exception, msg:
   # get the traceback object
    tb = sys.exc_info()[2]
    # tbinfo contains the line number that the code failed on and the code from that line
    tbinfo = traceback.format_tb(tb)[0]
    # concatenate information together concerning the error into a message string
    pymsg = "PYTHON ERRORS:\nTraceback Info:\n" + tbinfo + "\nError Info:\n    " + \
        str(sys.exc_type)+ ": " + str(sys.exc_value) + "\n"
    # generate a message string for any geoprocessing tool errors
    msgs = "GP ERRORS:\n" + gp.GetMessages(2) + "\n"
    gp.AddError(msgs)

    # return gp messages for use with a script tool
    gp.AddError(pymsg)

    # print messages for use in Python/PythonWin
    print pymsg
    print msgs
    raise