Get list of just files

This is a discussion on Get list of just files within the C Programming forums, part of the General Programming Boards category; I'm trying to find a way to get a list of only the files inside a directory. If that directory ...

  1. #1
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    Get list of just files

    I'm trying to find a way to get a list of only the files inside a directory. If that directory has other sub-directories in it, I don't want them in the list.

    I'm currently using scandir like this:

    char *pathname = "/var/";

    int count, i;
    struct direct **files;

    count = scandir(pathname, &files, file_select, alphasort);

    for (i=1; i<count+1; ++i)
    printf("%s\n", files[i-1]->d_name);

    I've looked around and can't find an easy way to check to see if an element in files is a directory or a file.

    Can anyone give me a suggestion?

    First time poster.

  2. #2
    Deathray Engineer MacGyver's Avatar
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    There is no portable way to do it really. Depends on what OS you are using and such.

  3. #3
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    oops

    forgot that part.

    I'm using debian linux

  4. #4
    and the hat of wrongness Salem's Avatar
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    So what does your file_select function do at the moment?

    It gets passed a pointer to a dirent, from which it should be easy to detect whether it's a directory or not.

    > for (i=1; i<count+1; ++i)
    So what's wrong with
    for (i=0; i<count; ++i)
    and removing the -1 inside the loop?
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    You're right

    I was focused more on the directory part and didn't realize I had a brain fart. I had copied some code I found online and hadn't really looked at it. - Thank you for not just laughing at me, but correcting me as well. I can deal with laughter. I can't stand my own laziness.

    So, how would you easily detect whether or not it's a directory. I've looking at doing something with a system call like "file *" or "ls -d */" and pipe it to a variable then split up the results then, but that sounds too ugly.

    My whole purpose for this is to run diff on every file, but not sub-directories against a "supposedly" duplicate file structure to look for any changes in files.

    Any pointers would be greatly appreciated.

    Thank you.

  6. #6
    and the Hat of Guessing tabstop's Avatar
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    My pointer is to type "man dirent", and examine the d_type field of the structure.

  7. #7
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    Thank you

    I see now that in my sample code adding files[i]->file_type to my code will get me what I need. If it returns a 4, it's a directory.

    Thank you for smackin' me upside my head.

  8. #8
    int x = *((int *) NULL); Cactus_Hugger's Avatar
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    If it returns a 4, it's a directory.
    You might to still read the documentation. There is probably a #define that you should be using. No writing of magic 4's into code.

    Furthermore, file_type might be a bitmask of various things ... 4 might not be the only thing to be a directory. (Like, a symlink pointing to a directory might have both bits set, and != 4.)

    There is no portable way to do it really. Depends on what OS you are using and such.
    stat() isn't portable? (Does opendir, stat, & friends only work on Mingw/every compiler but MSVC++?)
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  9. #9
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    I'd advise you to use stat(2) and then use the macro S_ISDIR to filter out all the directories. Please refer to the man page of stat(2) for more information.

  10. #10
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    Cactus_Hugger - I did take your pointer and read the documentation and I did end up using the #define DT_DIR instead of 4. That seems to be working.

    I will also read the docs for stat() like you and mageshd84 seem to indicate.

    I haven't done C in Linux for sometime so I had totally forgot about reading the man pages. I won't make that mistake again.

    I remember struggling through programming back in the days before Al Gore invented the Internet. Sometimes I fall victim to relying on asking questions rather than seeking answers on my own.

    Thank you to all who answered here.

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