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copied!<p>You need to check the return status of your system calls, and specifically <code>stat()</code>.</p> <p>What's happening is that you read a name found in the <code>..</code> directory, but when you invoke <code>stat()</code>, you are doing so on <code>./name</code> and not <code>../name</code>.</p> <p>This code should demonstrate the point:</p> <pre><code>#include <dirent.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/stat.h> #include <unistd.h> #include <errno.h> void print_dir(char *dir_n, char *file) { DIR *dir = opendir(dir_n); if (dir == 0) { int errnum = errno; fprintf(stderr, "error: opendir(\"%s\") failed (%d: %s)\n", dir_n, errnum, strerror(errnum)); exit(1); } struct dirent *Dirent; while ((Dirent = readdir(dir)) != 0) { struct stat stats; if (stat(Dirent->d_name, &stats) < 0) { int errnum = errno; fprintf(stderr, "error: failed to stat(\"%s\") (%d: %s)\n", Dirent->d_name, errnum, strerror(errnum)); } else if (S_ISDIR(stats.st_mode)) { if (strcmp(file, Dirent->d_name) == 0) { printf("found directory %s (inode = %ld)\n", Dirent->d_name, (long)stats.st_ino); break; } else printf("found directory %s - not a match for %s\n", Dirent->d_name, file); } else { printf("%s is not a directory\n", Dirent->d_name); } } closedir(dir); } int main(void) { print_dir("..", "dirtest"); return 0; } </code></pre> <p>And this trivial variant should find the directory <code>../dirtest</code> if it exists:</p> <pre><code>#include <dirent.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/stat.h> #include <unistd.h> #include <errno.h> void print_dir(char *dir_n, char *file) { DIR *dir = opendir(dir_n); if (dir == 0) { int errnum = errno; fprintf(stderr, "error: opendir(\"%s\") failed (%d: %s)\n", dir_n, errnum, strerror(errnum)); exit(1); } struct dirent *Dirent; while ((Dirent = readdir(dir)) != 0) { char fullname[1024]; snprintf(fullname, sizeof(fullname), "%s/%s", dir_n, Dirent->d_name); struct stat stats; if (stat(fullname, &stats) < 0) { int errnum = errno; fprintf(stderr, "error: failed to stat(\"%s\") (%d: %s)\n", fullname, errnum, strerror(errnum)); } else if (S_ISDIR(stats.st_mode)) { if (strcmp(file, Dirent->d_name) == 0) { printf("found directory %s (%s) (inode = %ld)\n", Dirent->d_name, fullname, (long)stats.st_ino); break; } else printf("found directory %s - not a match for %s\n", fullname, file); } else { printf("%s is not a directory\n", fullname); } } closedir(dir); } int main(void) { print_dir("..", "dirtest"); return 0; } </code></pre>

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