确定链接指向的目录条目的类型

Question

I want to read subdirectories and links to subdirectories only. With the following code I read all subdirs and links.

struct dirent* de;
DIR* dir = opendir(c_str());
if (!dir) { /* error handling */ }

while (NULL != (de = readdir(dir))) {
    if (de->d_type != DT_DIR && de->d_type != DT_LNK)
        continue;
    // Do something with subdirectory
 }

But how do I examine whether the link points to a subdirectory too? I do not want to read the entire linked directory to do this.

Answer 1

You can use function named stat from <sys/stat.h> :

struct dirent* de;
struct stat s;
DIR* dir = opendir(c_str());
if (!dir) { /* error handling */ }

while (NULL != (de = readdir(dir))) {
    if (de->d_type != DT_DIR) {
        char filename[256];
        sprintf(filename, "%s/%s", c_str(), de->d_name);
        if (stat(filename, &s) < 0)
            continue;
        if (!S_ISDIR(s.st_mode))
            continue;
    }
    // Do something with subdirectory
}