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xlistdir -- an iterator version of os.listdir

Chris Gonnerman chris.gonnerman at newcenturycomputers.net
Sun Jan 26 17:30:28 EST 2003 
----- Original Message -----
From: "Terrel Shumway" <tshumway at jdiworks.net>


> xlistdir.xlistdir is an iterator version of os.listdir.
>
> It is particularly useful if you have a directory with, for example,
> 40,000 files, and you only want to look at the first 10.
>
>   from xlistdir import xlistdir
>   x = xlistdir("directory-with-LOTS-of-files")
>
>   for i in range(10):
>       print x[i] # or "x.next()"
>
>
> You might also use it to filter the list before allocating it:
>
>   files_only = [ file for file in xlistdir(bigdir) \
> if os.path.isfile(os.path.join(bigdir,file)) ]
>
>
> Most of this code was cut and pasted from xreadlinesmodule.c and
posixmodule.c
> in Python-2.2.2.tgz
>
> This initial hack may not even compile on platforms without
> opendir/readdir/closedir (e.g. mswin32, mswin16, OS/2) because I do
> not have access to those platforms.

I tried it using MinGW32 on Win98... after putting in an
apparently-missing #include <windows.h>, here is what I got:

C:\WINDOWS\Desktop\xlistdir-0.1>python setup.py build --compiler=mingw32
running build
running build_py
not copying test_xlistdir.py (output up-to-date)
running build_ext
building 'xlistdir' extension
C:\MINGW32\BIN\gcc.exe -mno-cygwin -mdll -O -Wall -IC:\PYTHON\include -c
xlistdi
rmodule.c -o build\temp.win32-2.2\Release\xlistdirmodule.o
xlistdirmodule.c: In function `xlistdir_opendir':
xlistdirmodule.c:83: warning: implicit declaration of function `win32_error'
xlistdirmodule.c:83: warning: return makes pointer from integer without a
cast
xlistdirmodule.c:57: warning: unused variable `bufptr'
xlistdirmodule.c: In function `xlistdir_closedir':
xlistdirmodule.c:104: `op' undeclared (first use in this function)
xlistdirmodule.c:104: (Each undeclared identifier is reported only once
xlistdirmodule.c:104: for each function it appears in.)
xlistdirmodule.c:110: warning: return makes pointer from integer without a
cast
xlistdirmodule.c: In function `xlistdir_readdir':
xlistdirmodule.c:119: `op' undeclared (first use in this function)
xlistdirmodule.c:123: structure has no member named `cFilename'
xlistdirmodule.c:128: warning: suggest parentheses around && within ||
error: command 'gcc' failed with exit status 1


> It does include a unit test, and it does pass for me on Linux. 8-)
>
> If you can build extension modules on MS_WIN32, MS_WIN16, or OS/2 (or
others),
> please try this out.  If you can make it compile and pass the unit tests,
> you will get a really cool function to use in your programs and share with
> the rest of the python community 8-).

Chris Gonnerman -- chris.gonnerman at newcenturycomputers.net
http://newcenturycomputers.net
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