[Python-talk] Beginning of a cheesy file navigator... Why does it do ...

[Bruce Labitt]

I have the beginnings of a file navigation module that I want to embed 
in some other code I have written.  Umm, it almost works.  Here is the 
latest version.  Questions at bottom.

==== start code ===============================================
#!/usr/bin/env python
import shutil
import sys, os, string

"""
Program to navigate to proper data file
Author: Bruce Labitt
Copyright 2009 by Bruce Labitt
Date: 3 July 2009
"""

def myfilenavigate( ):
  currentdir = os.getcwd()  # save current directory
 
  baddir = 1
  while (baddir ==1):
    dirflag = 1
   
    while (dirflag==1):
      try:
        yorn = raw_input('Is your data in the default drive? (y) or n ==> ')
        if (yorn == 'n'):
          mydatadir = raw_input('Enter the data subdir ==> ')
          # use double \ for directory separators.  why? that's what 
works...
        else:
          mydatadir = 'c:\\Python25\\mytec'
         
        os.chdir(mydatadir)    # change directory to mydatadir
      except (IOError, NameError):
        print 'Subdirectory does not exist, try again!'
        mydatadir = raw_input('Enter a valid data subdirectory ==> ')
      else:
        dirflag = 0
   
    print 'Listing of data subdirectory'
    os.system('dir *.dat')  # DOS system command
    rightdir = raw_input('In the right dir? (y) or n ==> ')
    if (rightdir =='n'):
      baddir = 1
      dirflag = 1
    else:
      baddir  = 0  # set to get out of baddir loop
      badfile = 1
      print
      while (badfile == 1):  # stay in loop until we get a good file name
        try:
          filename = raw_input('Enter filename ==> ')
          f1 = open(filename, 'rb')
        except (IOError, NameError):
          print 'File does not exist, try again!'
        else:
          print 'File opened for reading'
          badfile = 0   # gets out of loop
 
 
  os.chdir(currentdir)  # put the directory back
  return f1

==== end code 
===============================================================

Here is a snippet of the run:
===============================================
In [13]: %run tecgtreadermb.py
Is your data in the default drive? (y) or n n
Enter the data subdir ==> g:\python_stuff
Listing of data subdirectory
 Volume in drive G has no label.
 Volume Serial Number is 0000-1F3B

 Directory of g:\python_stuff

11/10/2008  05:57 PM         3,199,616 test.dat
               1 File(s)      3,199,616 bytes
               0 Dir(s)   1,558,749,184 bytes free
In the right dir? (y) or n ==> n
Listing of data subdirectory
 Volume in drive G has no label.
 Volume Serial Number is 0000-1F3B

 Directory of g:\python_stuff

11/10/2008  05:57 PM         3,199,616 test.dat
               1 File(s)      3,199,616 bytes
               0 Dir(s)   1,558,749,184 bytes free
In the right dir? (y) or n ==>
================================================

As you can see, taking the non-default path results in going thru the
while(baddir==1) loop, but not thru the while(dirflag==1) loop?

Can anyone point me in the right direction?

If I take the defaults, everything seems to work as expected...

-Bruce