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with open("foo", "w") as f: pass
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import os
for root, dirs, files in os.walk("C:/"):
for i in files:
print root + "\\" + i
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"""Modified version of shutil.copytree for copytree with empty files"""
#Markierung 1 -> emptycopy muss erstellt werden
#Markierung 2 -> statt copy2(srcname, dstname) -> emptycopy(srcname, dstname)
import os
import stat
import errno
class Error(EnvironmentError):
pass
class SpecialFileError(EnvironmentError):
"""Raised when trying to do a kind of operation (e.g. copying) which is
not supported on a special file (e.g. a named pipe)"""
class ExecError(EnvironmentError):
"""Raised when a command could not be executed"""
try:
WindowsError
except NameError:
WindowsError = None
def copyfileobj(fsrc, fdst, length=16*1024):
"""copy data from file-like object fsrc to file-like object fdst"""
while 1:
buf = fsrc.read(length)
if not buf:
break
fdst.write(buf)
def _samefile(src, dst):
# Macintosh, Unix.
if hasattr(os.path, 'samefile'):
try:
return os.path.samefile(src, dst)
except OSError:
return False
# All other platforms: check for same pathname.
return (os.path.normcase(os.path.abspath(src)) ==
os.path.normcase(os.path.abspath(dst)))
def copyfile(src, dst):
"""Copy data from src to dst"""
if _samefile(src, dst):
raise Error("`%s` and `%s` are the same file" % (src, dst))
for fn in [src, dst]:
try:
st = os.stat(fn)
except OSError:
# File most likely does not exist
pass
else:
# XXX What about other special files? (sockets, devices...)
if stat.S_ISFIFO(st.st_mode):
raise SpecialFileError("`%s` is a named pipe" % fn)
with open(src, 'rb') as fsrc:
with open(dst, 'wb') as fdst:
copyfileobj(fsrc, fdst)
def copystat(src, dst):
"""Copy all stat info (mode bits, atime, mtime, flags) from src to dst"""
st = os.stat(src)
mode = stat.S_IMODE(st.st_mode)
if hasattr(os, 'utime'):
os.utime(dst, (st.st_atime, st.st_mtime))
if hasattr(os, 'chmod'):
os.chmod(dst, mode)
if hasattr(os, 'chflags') and hasattr(st, 'st_flags'):
try:
os.chflags(dst, st.st_flags)
except OSError, why:
if (not hasattr(errno, 'EOPNOTSUPP') or
why.errno != errno.EOPNOTSUPP):
raise
def copy2(src, dst):
"""Copy data and all stat info ("cp -p src dst").
The destination may be a directory.
"""
if os.path.isdir(dst):
dst = os.path.join(dst, os.path.basename(src))
copyfile(src, dst)
copystat(src, dst)
def emptycopy(src, dst):
"""Create empty file with src name.
Copy file, when file extension in files=[]."""
#1. Markierung
files = ["txt", "py", "pdf", "doc", "odt"]
open(dst, "w").close()
for i in files:
if src[-3:] == i:
copy2(src, dst)
elif src[-2:] == i:
copy2(src, dst)
def copytree(src, dst, symlinks=False, ignore=None):
"""Recursively copy a directory tree with empty files using emptycopy().
"""
names = os.listdir(src)
if ignore is not None:
ignored_names = ignore(src, names)
else:
ignored_names = set()
os.makedirs(dst)
errors = []
for name in names:
if name in ignored_names:
continue
srcname = os.path.join(src, name)
dstname = os.path.join(dst, name)
try:
if symlinks and os.path.islink(srcname):
linkto = os.readlink(srcname)
os.symlink(linkto, dstname)
elif os.path.isdir(srcname):
copytree(srcname, dstname, symlinks, ignore)
else:
# Will raise a SpecialFileError for unsupported file types
#2. Markierung
emptycopy(srcname, dstname)
# catch the Error from the recursive copytree so that we can
# continue with other files
except Error, err:
errors.extend(err.args[0])
except EnvironmentError, why:
errors.append((srcname, dstname, str(why)))
try:
copystat(src, dst)
except OSError, why:
if WindowsError is not None and isinstance(why, WindowsError):
# Copying file access times may fail on Windows
pass
else:
errors.extend((src, dst, str(why)))
if errors:
raise Error, errors
Eine Lösung für schneller zu *halten* ist selten ein guter Maßstab. Wenn, dann sollte man dies auch testen. Davon abgesehen ist das Trennen von Dateiendungen sicher kein Flaschenhals in der Anwendung. Und wenn doch, dann solltest du vielleicht nicht Python verwenden.Dami123 hat geschrieben:splittext hab ich mir überlegt, halte aber [-3:] für schneller. Wenn man viele extensions rauskopieren möchte, ist esd aber die bessere Lösung, ja.
Relevante Beispiele für Dateiendungen an denen das scheitert: .html und .py.BlackJack hat geschrieben:Was an dem [-3:] IMHO unschön ist, ist die implizite Abhängigkeit von der/den Längen der Dateiendungen, die man weder bei `endswith()` noch `splitext()` hat. Und ob nun `splitext()` und ein `set()` mit Dateiendungen oder `endswith()` mit einem Tupel schneller ist, müsste man Messen wenn es einen interessiert.
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edit_shutil.treefiles(src, dst, exten=(".txt", ".html"))Code: Alles auswählen
def treefiles(src, dst, exten, symlinks=False, ignore=None):
"""Copy all files with defined extensions from a directory."""
names = os.listdir(src)
try:
names.remove("$RECYCLE.BIN")
names.remove("System Volume Information")
except:
pass
if ignore is not None:
ignored_names = ignore(src, names)
else:
ignored_names = set()
errors = []
for name in names:
if name in ignored_names:
continue
srcname = os.path.join(src, name)
dstname = dst
try:
if symlinks and os.path.islink(srcname):
linkto = os.readlink(srcname)
os.symlink(linkto, dstname)
elif os.path.isdir(srcname):
treefiles(srcname, dstname, exten, symlinks, ignore)
else:
# Will raise a SpecialFileError for unsupported file types
try:
if srcname.endswith(exten):
copy2(srcname, dst)
except:
pass
# catch the Error from the recursive copytree so that we can
# continue with other files
except Error, err:
errors.extend(err.args[0])
except EnvironmentError, why:
errors.append((srcname, dstname, str(why)))
try:
copystat(src, dst)
except OSError, why:
if WindowsError is not None and isinstance(why, WindowsError):
# Copying file access times may fail on Windows
pass
else:
errors.extend((src, dst, str(why)))
if errors:
copyonly(srcname, dstname, symlinks, ignore)
raise Error, errors
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def treefiles(src, dst, exten, symlinks=False, ignore=None, ignored_names = ("$RECYCLE.BIN", "System Volume Information")):
"""Copy all files with defined extensions from a directory."""
names = os.listdir(src)
ignored_names = set(ignored_names) | set(() if ignore is None else ignore(src, names))
usw.