The <ftw.h> header defines the FTW structure that includes the following members:
int base int level
The <ftw.h> header defines macros for use as values of the third argument to the application-supplied function that is passed as the second argument to ftw() and nftw() (see ftw(3C)):
directory without read permission
directory with subdirectories visited
unknown type; stat() failed
symbolic link that names a nonexistent file
The <ftw.h> header defines macros for use as values of the fourth argument to nftw():
Physical walk, does not follow symbolic links. Otherwise, nftw() follows links but does not walk down any path that crosses itself.
The walk does not cross a mount point.
All subdirectories are visited before the directory itself.
The walk changes to each direct ory before reading it.
The <ftw.h> header defines the stat structure and the symbolic names for st_mode and the file type test macros as described in <sys/stat.h>.
Inclusion of the <ftw.h> header might also make visible all symbols from <sys/stat.h>.
See attributes(5) for descriptions of the following attributes: