Running the build script changes its ctime

[GoogleCodeExporter]

What steps will reproduce the problem?

$ cat > foo.py
from fabricate import *

def build():
        run('touch', 'bar')

main()
$ stat foo.py
234881026 59660628 -rw-r--r-- 1 ljosa broad 0 67 "Sep 10 13:40:08 2009" "Sep 10 
13:40:06 
2009" "Sep 10 13:40:06 2009" "Sep 10 13:40:04 2009" 4096 8 0 foo.py
$ python foo.py
touch bar
$ stat foo.py
234881026 59660628 -rw-r--r-- 1 ljosa broad 0 67 "Sep 10 13:40:13 2009" "Sep 10 
13:40:06 
2009" "Sep 10 13:40:13 2009" "Sep 10 13:40:04 2009" 4096 8 0 foo.py

What is the expected output? What do you see instead?

I expected ctime to stay the same.  Instead it has been updated to the current 
time.

What version of the product are you using? On what operating system?

Fabricate 1.08 on Mac OS X 10.5.8.

Please provide any additional information below.

This is a problem mainly because emacs will complain that "foo.py changed on 
disk; really edit 
the buffer?" the next time I try to edit the already open buffer.

Original issue reported on code.google.com by lj...@pvv.ntnu.no on 10 Sep 2009 at 5:45

[GoogleCodeExporter]

This is a strange problem.  Doesn't happen on linux; only mac, apparently.  Does
python usually change the ctime when it runs a script on the mac?  If not, be 
good if
you can isolate further exactly what part of fabricate changes the ctime.

Original comment by berh...@gmail.com on 14 Oct 2009 at 4:44