[Haskell-cafe] [Beginner's Question] How to read filenames from a DirStream

[Jeremy Shaw]

Hello,

This multipart tutorial seems similar to what you are describing:

http://blog.moertel.com/articles/2007/03/28/directory-tree-printing-in-haskell-part-three-lazy-i-o

The tutorial is actually a bit more complicated, it is traversing a
whole directory tree and printing a nice graph. 

HTH,
j.

At Mon, 9 Apr 2007 10:46:14 +0800,
Albert Lee wrote:
> 
> Newbie's question: I want to ls the filenames of a directory. The program in
> C is something like:
> 
> #include <direnet.h>
> 
> int main(){
>    DIR  *dp;
>    struct dirent *dirp;
> 
>    dp = opendir("/");
> 
>    while((dirp = readdir(dp)) != NULL)
>        printf("%s\n", dirp->d_name);
> 
>    closedir(dp);
> }
> 
> 
> and I write that in haskell:
> 
> -----
> import System.Posix
> import System.IO
> 
> main = do
>     dp <- openDirStream "/"
>     df <- readDirStream dp
>     putStrLn df
>     closeDirStream dp
> 
> 
> ------
> It can print the first entry of the dir, but how can we list it all like the
> C prog?  map ? list comperhension?