Advanced UNIX Programming

Walking a Directory Structure

Some UNIX platforms provide the function ftw(3C) and the newer function nftw(3C) to make it simpler to perform a tree walk of a file system. These functions do not appear on the FreeBSD system, so only a cursory description of them will be provided here. The HPUX-11 ftw(3C) page provides this function synopsis:

#include <ftw.h>

int ftw (const char *path,
    int (*fn)(const char *obj_path,
        const struct stat *obj_stat,
        int obj_flags),
    int depth);

int nftw (const char *path,
    int (*fn)(const char *obj_path,
        const struct stat *obj_stat,
        int obj_flags,
        struct FTW obj_FTW),
    int depth,
    int flags);

These functions start by examining the directory provided by the argument path. From this point on, the directory is recursively ...