os模組提供了對目錄或者檔案的建立/刪除/查看檔案屬性,還提供了對檔案以及目錄的路徑操作。比如說:絕對路徑,父目錄…… 但是,os檔案的操作還應該包含移動 複製 打包 壓縮 解壓等操作,這些os模組都沒有提供。
而本文所講的shutil則就是對os中檔案操作的補充。--移動 複製 打包 壓縮 解壓,
shutil函數功能:
1 shutil.copyfileobj(fsrc, fdst[, length=16*1024])
copy檔案內容到另一個檔案,可以copy指定大小的內容
先來看看其原始碼。
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)
注意! 在其中fsrc,fdst都是檔案對象,都需要開啟後才能進行複製操作
import shutilf1=open('name','r')f2=open('name_copy','w+')shutil.copyfileobj(f1,f2,length=16*1024)
2 shutil.copyfile(src,dst)
copy檔案內容,是不是感覺上面的檔案複製很麻煩?還需要自己手動用open函數開啟檔案,在這裡就不需要了,事實上,copyfile調用了copyfileobj
def copyfile(src, dst, *, follow_symlinks=True): if _samefile(src, dst): raise SameFileError("{!r} and {!r} are the same file".format(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) if not follow_symlinks and os.path.islink(src): os.symlink(os.readlink(src), dst) else: with open(src, 'rb') as fsrc: with open(dst, 'wb') as fdst: copyfileobj(fsrc, fdst) return dst
shutil.copyfile('name','name_copy_2')#一句就可以實現複製檔案內容
3 shutil.copymode(src,dst)
僅copy許可權,不變更檔內容,組和使用者。
def copymode(src, dst, *, follow_symlinks=True): if not follow_symlinks and os.path.islink(src) and os.path.islink(dst): if hasattr(os, 'lchmod'): stat_func, chmod_func = os.lstat, os.lchmod else: return elif hasattr(os, 'chmod'): stat_func, chmod_func = os.stat, os.chmod else: return st = stat_func(src) chmod_func(dst, stat.S_IMODE(st.st_mode))
先看兩個檔案的許可權
[root@slyoyo python_test]# ls -ltotal 4-rw-r--r--. 1 root root 79 May 14 05:17 test1-rwxr-xr-x. 1 root root 0 May 14 19:10 test2
運行命令
>>> import shutil>>> shutil.copymode('test1','test2')
查看結果
[root@slyoyo python_test]# ls -ltotal 4-rw-r--r--. 1 root root 79 May 14 05:17 test1-rw-r--r--. 1 root root 0 May 14 19:10 test2
當我們將目標檔案換為一個不存在的檔案時報錯
>>> shutil.copymode('test1','test3') Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/usr/local/python/lib/python3.4/shutil.py", line 132, in copymode chmod_func(dst, stat.S_IMODE(st.st_mode))FileNotFoundError: [Errno 2] No such file or directory: 'test233'
4 shutil.copystat(src,dst)
複製所有的狀態資訊,包括許可權,組,使用者,時間等
def copystat(src, dst, *, follow_symlinks=True): def _nop(*args, ns=None, follow_symlinks=None): pass # follow symlinks (aka don't not follow symlinks) follow = follow_symlinks or not (os.path.islink(src) and os.path.islink(dst)) if follow: # use the real function if it exists def lookup(name): return getattr(os, name, _nop) else: # use the real function only if it exists # *and* it supports follow_symlinks def lookup(name): fn = getattr(os, name, _nop) if fn in os.supports_follow_symlinks: return fn return _nop st = lookup("stat")(src, follow_symlinks=follow) mode = stat.S_IMODE(st.st_mode) lookup("utime")(dst, ns=(st.st_atime_ns, st.st_mtime_ns), follow_symlinks=follow) try: lookup("chmod")(dst, mode, follow_symlinks=follow) except NotImplementedError: # if we got a NotImplementedError, it's because # * follow_symlinks=False, # * lchown() is unavailable, and # * either # * fchownat() is unavailable or # * fchownat() doesn't implement AT_SYMLINK_NOFOLLOW. # (it returned ENOSUP.) # therefore we're out of options--we simply cannot chown the # symlink. give up, suppress the error. # (which is what shutil always did in this circumstance.) pass if hasattr(st, 'st_flags'): try: lookup("chflags")(dst, st.st_flags, follow_symlinks=follow) except OSError as why: for err in 'EOPNOTSUPP', 'ENOTSUP': if hasattr(errno, err) and why.errno == getattr(errno, err): break else: raise _copyxattr(src, dst, follow_symlinks=follow)
5 shutil.copy(src,dst)
複製檔案的內容以及許可權,先copyfile後copymode
def copy(src, dst, *, follow_symlinks=True): if os.path.isdir(dst): dst = os.path.join(dst, os.path.basename(src)) copyfile(src, dst, follow_symlinks=follow_symlinks) copymode(src, dst, follow_symlinks=follow_symlinks) return dst
6 shutil.copy2(src,dst)
複製檔案的內容以及檔案的所有狀態資訊。先copyfile後copystat
def copy2(src, dst, *, follow_symlinks=True): """Copy data and all stat info ("cp -p src dst"). Return the file's destination." The destination may be a directory. If follow_symlinks is false, symlinks won't be followed. This resembles GNU's "cp -P src dst". """ if os.path.isdir(dst): dst = os.path.join(dst, os.path.basename(src)) copyfile(src, dst, follow_symlinks=follow_symlinks) copystat(src, dst, follow_symlinks=follow_symlinks) return dst
7 shutil.copytree(src, dst, symlinks=False, ignore=None, copy_function=copy2,ignore_dangling_symlinks=False)
遞迴的複製檔案內容及狀態資訊
def copytree(src, dst, symlinks=False, ignore=None, copy_function=copy2, ignore_dangling_symlinks=False): 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 os.path.islink(srcname): linkto = os.readlink(srcname) if symlinks: # We can't just leave it to `copy_function` because legacy # code with a custom `copy_function` may rely on copytree # doing the right thing. os.symlink(linkto, dstname) copystat(srcname, dstname, follow_symlinks=not symlinks) else: # ignore dangling symlink if the flag is on if not os.path.exists(linkto) and ignore_dangling_symlinks: continue # otherwise let the copy occurs. copy2 will raise an error if os.path.isdir(srcname): copytree(srcname, dstname, symlinks, ignore, copy_function) else: copy_function(srcname, dstname) elif os.path.isdir(srcname): copytree(srcname, dstname, symlinks, ignore, copy_function) else: # Will raise a SpecialFileError for unsupported file types copy_function(srcname, dstname) # catch the Error from the recursive copytree so that we can # continue with other files except Error as err: errors.extend(err.args[0]) except OSError as why: errors.append((srcname, dstname, str(why))) try: copystat(src, dst) except OSError as why: # Copying file access times may fail on Windows if getattr(why, 'winerror', None) is None: errors.append((src, dst, str(why))) if errors: raise Error(errors) return dst# version vulnerable to race conditions
[root@slyoyo python_test]# tree copytree_test/copytree_test/└── test ├── test1 ├── test2 └── hahaha[root@slyoyo test]# ls -ltotal 0-rw-r--r--. 1 python python 0 May 14 19:36 hahaha-rw-r--r--. 1 python python 0 May 14 19:36 test1-rw-r--r--. 1 root root 0 May 14 19:36 test2>>> shutil.copytree('copytree_test','copytree_copy')'copytree_copy'[root@slyoyo python_test]# ls -ltotal 12drwxr-xr-x. 3 root root 4096 May 14 19:36 copytree_copydrwxr-xr-x. 3 root root 4096 May 14 19:36 copytree_test-rw-r--r--. 1 python python 79 May 14 05:17 test1-rw-r--r--. 1 root root 0 May 14 19:10 test2[root@slyoyo python_test]# tree copytree_copy/copytree_copy/└── test ├── hahaha ├── test1 └── test2
8 shutil.rmtree(path, ignore_errors=False, onerror=None)
遞迴地刪除檔案
def rmtree(path, ignore_errors=False, onerror=None): if ignore_errors: def onerror(*args): pass elif onerror is None: def onerror(*args): raise if _use_fd_functions: # While the unsafe rmtree works fine on bytes, the fd based does not. if isinstance(path, bytes): path = os.fsdecode(path) # Note: To guard against symlink races, we use the standard # lstat()/open()/fstat() trick. try: orig_st = os.lstat(path) except Exception: onerror(os.lstat, path, sys.exc_info()) return try: fd = os.open(path, os.O_RDONLY) except Exception: onerror(os.lstat, path, sys.exc_info()) return try: if os.path.samestat(orig_st, os.fstat(fd)): _rmtree_safe_fd(fd, path, onerror) try: os.rmdir(path) except OSError: onerror(os.rmdir, path, sys.exc_info()) else: try: # symlinks to directories are forbidden, see bug #1669 raise OSError("Cannot call rmtree on a symbolic link") except OSError: onerror(os.path.islink, path, sys.exc_info()) finally: os.close(fd) else: return _rmtree_unsafe(path, onerror)
9 shutil.move(src, dst)
遞迴的移動檔案
def move(src, dst): real_dst = dst if os.path.isdir(dst): if _samefile(src, dst): # We might be on a case insensitive filesystem, # perform the rename anyway. os.rename(src, dst) return real_dst = os.path.join(dst, _basename(src)) if os.path.exists(real_dst): raise Error("Destination path '%s' already exists" % real_dst) try: os.rename(src, real_dst) except OSError: if os.path.islink(src): linkto = os.readlink(src) os.symlink(linkto, real_dst) os.unlink(src) elif os.path.isdir(src): if _destinsrc(src, dst): raise Error("Cannot move a directory '%s' into itself '%s'." % (src, dst)) copytree(src, real_dst, symlinks=True) rmtree(src) else: copy2(src, real_dst) os.unlink(src) return real_dst
10 make_archive(base_name, format, root_dir=None, base_dir=None, verbose=0,dry_run=0, owner=None, group=None, logger=None)
壓縮打包
def make_archive(base_name, format, root_dir=None, base_dir=None, verbose=0, dry_run=0, owner=None, group=None, logger=None): save_cwd = os.getcwd() if root_dir is not None: if logger is not None: logger.debug("changing into '%s'", root_dir) base_name = os.path.abspath(base_name) if not dry_run: os.chdir(root_dir) if base_dir is None: base_dir = os.curdir kwargs = {'dry_run': dry_run, 'logger': logger} try: format_info = _ARCHIVE_FORMATS[format] except KeyError: raise ValueError("unknown archive format '%s'" % format) func = format_info[0] for arg, val in format_info[1]: kwargs[arg] = val if format != 'zip': kwargs['owner'] = owner kwargs['group'] = group try: filename = func(base_name, base_dir, **kwargs) finally: if root_dir is not None: if logger is not None: logger.debug("changing back to '%s'", save_cwd) os.chdir(save_cwd) return filename
base_name: 壓縮打包後的檔案名稱或者路徑名
format: 壓縮或者打包格式 "zip", "tar", "bztar"or "gztar"
root_dir : 將哪個目錄或者檔案打包(也就是源檔案)
>>> shutil.make_archive('tarball','gztar',root_dir='copytree_test')[root@slyoyo python_test]# ls -ltotal 12drwxr-xr-x. 3 root root 4096 May 14 19:36 copytree_copydrwxr-xr-x. 3 root root 4096 May 14 19:36 copytree_test-rw-r--r--. 1 root root 0 May 14 21:12 tarball.tar.gz-rw-r--r--. 1 python python 79 May 14 05:17 test1-rw-r--r--. 1 root root 0 May 14 19:10 test2