Issue #15177: Added dir_fd parameter to os.fwalk().
diff --git a/Lib/os.py b/Lib/os.py
index f990627..381737f 100644
--- a/Lib/os.py
+++ b/Lib/os.py
@@ -422,9 +422,9 @@
__all__.append("walk")
-if open in supports_dir_fd:
+if {open, stat} <= supports_dir_fd and {listdir, stat} <= supports_fd:
- def fwalk(top, topdown=True, onerror=None, followlinks=False):
+ def fwalk(top=".", topdown=True, onerror=None, followlinks=False, *, dir_fd=None):
"""Directory tree generator.
This behaves exactly like walk(), except that it yields a 4-tuple
@@ -434,9 +434,13 @@
`dirpath`, `dirnames` and `filenames` are identical to walk() output,
and `dirfd` is a file descriptor referring to the directory `dirpath`.
- The advantage of walkfd() over walk() is that it's safe against symlink
+ The advantage of fwalk() over walk() is that it's safe against symlink
races (when followlinks is False).
+ If dir_fd is not None, it should be a file descriptor open to a directory,
+ and top should be relative; top will then be relative to that directory.
+ (dir_fd is always supported for fwalk.)
+
Caution:
Since fwalk() yields file descriptors, those are only valid until the
next iteration step, so you should dup() them if you want to keep them
@@ -455,11 +459,11 @@
"""
# Note: To guard against symlink races, we use the standard
# lstat()/open()/fstat() trick.
- orig_st = lstat(top)
- topfd = open(top, O_RDONLY)
+ orig_st = stat(top, follow_symlinks=False, dir_fd=dir_fd)
+ topfd = open(top, O_RDONLY, dir_fd=dir_fd)
try:
if (followlinks or (st.S_ISDIR(orig_st.st_mode) and
- path.samestat(orig_st, fstat(topfd)))):
+ path.samestat(orig_st, stat(topfd)))):
yield from _fwalk(topfd, top, topdown, onerror, followlinks)
finally:
close(topfd)
@@ -502,7 +506,7 @@
onerror(err)
return
try:
- if followlinks or path.samestat(orig_st, fstat(dirfd)):
+ if followlinks or path.samestat(orig_st, stat(dirfd)):
dirpath = path.join(toppath, name)
yield from _fwalk(dirfd, dirpath, topdown, onerror, followlinks)
finally: