How do you determine using stat() whether a file is a symbolic link?

问题

I basically have to write a clone of the UNIX ls command for a class, and I've got almost everything working. One thing I can't seem to figure out how to do is check whether a file is a symbolic link or not. From the man page for stat(), I see that there is a mode_t value defined, S_IFLNK.

This is how I'm trying to check whether a file is a sym-link, with no luck (note, stbuf is the buffer that stat() returned the inode data into):

switch(stbuf.st_mode & S_IFMT){
    case S_IFLNK:
        printf("this is a link\n");
        break;
    case S_IFREG:
        printf("this is not a link\n");
        break;
}

My code ALWAYS prints this is not a link even if it is, and I know for a fact that the said file is a symbolic link since the actual ls command says so, plus I created the sym-link...

Can anyone spot what I may be doing wrong? Thanks for the help!

回答1:

You can't.

You need to use lstat() to stat the link itself, plain stat() will follow the link, and thus never "see" the link itself.

来源：https://stackoverflow.com/questions/2635923/how-do-you-determine-using-stat-whether-a-file-is-a-symbolic-link