FTW(3)              Linux Programmer's Manual              FTW(3)

       ftw - file tree walk

       #include <ftw.h>

       int  ftw(const char *directory, int (*funcptr )(const char
       *file, struct stat *sb, int flag), int depth);

       ftw() walks through the directory tree starting  from  the
       indicated directory.  For each found entry in the tree, it
       calls funcptr with the full pathname of the entry relative
       to  directory,  a  pointer  to  a the second argument is a
       pointer to the stat(2) structure for the entry and an int,
       which value will be one of the following:
              FTW_F     Item is a normal file
              FTW_D     Item is a directory
              FTW_NS    The stat failed on the item
              FTW_DNR   Item is a directory which can't be read
       Warning:  Anything  other  than directories, like symbolic
       links, gets the FTW_F tag.

       ftw() recursively calls itself for traversing found direc-
       tories.   To  avoid using up all a program's file descrip-
       tors, the depth specifies the number of simultaneous  open
       directories.   When  the  depth  is  exceeded,  ftw() will
       become slower because directories have to  be  closed  and

       To  stop  the tree walk, funcptr returns a non-zero value;
       this value will become the return value of ftw().   Other-
       wise,  ftw()  will  continue  until  it  has traversed the
       entire tree, in which case it will return zero,  or  until
       it  hits  an  error  such as a malloc(3) failure, in which
       case it will return -1.

       Because ftw() uses dynamic data structures, the only  safe
       way  to  exit  out  of a tree walk is to return a non-zero
       value.  To handle interrupts, for example, mark  that  the
       interrupt  occurred and return a non-zero value--don't use
       longjmp(3) unless the program is going to terminate.

       AES, SVID2, SVID3, XPG2, XPG3, XPG4


Linux                     July 18, 1993                         1