A macro for iterating over the contents of a directory.

for_dir.h

#include <dirent.h>

#define for_dir(entry, dirname, continuation)        \
    do {                                             \
        DIR* for_dir_dir__ = opendir(dirname);       \
        for (struct dirent* (entry);                 \
             ((entry) = readdir(for_dir_dir__));) {  \
            continuation                             \
        }                                            \
        closedir(for_dir_dir__);                     \
    } while (0);