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  2. 函数列表
  3. errno.ENODATA

Python errno 模块，ENODATA 实例源码

我们从Python开源项目中，提取了以下23个代码示例，用于说明如何使用errno.ENODATA。

项目：python-    作者：secondtonone1    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：ivaochdoc    作者：ivaoch    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：news-for-good    作者：thecodinghub    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：Tencent_Cartoon_Download    作者：Fretice    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：fieldsight-kobocat    作者：awemulya    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：web_ctp    作者：molebot    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：CloudPrint    作者：William-An    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：ouroboros    作者：pybee    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：gardenbot    作者：GoestaO    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：projeto    作者：BarmyPenguin    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：flask-zhenai-mongo-echarts    作者：Fretice    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：aweasome_learning    作者：Knight-ZXW    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：kbe_server    作者：xiaohaoppy    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：blog_flask    作者：momantai    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：MyFriend-Rob    作者：lcheniv    | 项目源码 | 文件源码 
def _copyxattr(src, dst, *, follow_symlinks=True):
        """Copy extended filesystem attributes from `src` to `dst`.

        Overwrite existing attributes.

        If `follow_symlinks` is false, symlinks won't be followed.

        """

        try:
            names = os.listxattr(src, follow_symlinks=follow_symlinks)
        except OSError as e:
            if e.errno not in (errno.ENOTSUP, errno.ENODATA):
                raise
            return
        for name in names:
            try:
                value = os.getxattr(src, name, follow_symlinks=follow_symlinks)
                os.setxattr(dst, name, value, follow_symlinks=follow_symlinks)
            except OSError as e:
                if e.errno not in (errno.EPERM, errno.ENOTSUP, errno.ENODATA):
                    raise
项目：web_ctp    作者：molebot    | 项目源码 | 文件源码 
def _check_xattrs_str(self, s, getxattr, setxattr, removexattr, listxattr, **kwargs):
        fn = support.TESTFN
        open(fn, "wb").close()
        with self.assertRaises(OSError) as cm:
            getxattr(fn, s("user.test"), **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        init_xattr = listxattr(fn)
        self.assertIsInstance(init_xattr, list)
        setxattr(fn, s("user.test"), b"", **kwargs)
        xattr = set(init_xattr)
        xattr.add("user.test")
        self.assertEqual(set(listxattr(fn)), xattr)
        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"")
        setxattr(fn, s("user.test"), b"hello", os.XATTR_REPLACE, **kwargs)
        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"hello")
        with self.assertRaises(OSError) as cm:
            setxattr(fn, s("user.test"), b"bye", os.XATTR_CREATE, **kwargs)
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        with self.assertRaises(OSError) as cm:
            setxattr(fn, s("user.test2"), b"bye", os.XATTR_REPLACE, **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        setxattr(fn, s("user.test2"), b"foo", os.XATTR_CREATE, **kwargs)
        xattr.add("user.test2")
        self.assertEqual(set(listxattr(fn)), xattr)
        removexattr(fn, s("user.test"), **kwargs)
        with self.assertRaises(OSError) as cm:
            getxattr(fn, s("user.test"), **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        xattr.remove("user.test")
        self.assertEqual(set(listxattr(fn)), xattr)
        self.assertEqual(getxattr(fn, s("user.test2"), **kwargs), b"foo")
        setxattr(fn, s("user.test"), b"a"*1024, **kwargs)
        self.assertEqual(getxattr(fn, s("user.test"), **kwargs), b"a"*1024)
        removexattr(fn, s("user.test"), **kwargs)
        many = sorted("user.test{}".format(i) for i in range(100))
        for thing in many:
            setxattr(fn, thing, b"x", **kwargs)
        self.assertEqual(set(listxattr(fn)), set(init_xattr) | set(many))
项目：ouroboros    作者：pybee    | 项目源码 | 文件源码 
def _check_xattrs_str(self, s, getxattr, setxattr, removexattr, listxattr, **kwargs):
        fn = support.TESTFN
        open(fn, "wb").close()
        with self.assertRaises(OSError) as cm:
            getxattr(fn, s("user.test"), **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        init_xattr = listxattr(fn)
        self.assertIsInstance(init_xattr, list)
        setxattr(fn, s("user.test"), b"", **kwargs)
        xattr = set(init_xattr)
        xattr.add("user.test")
        self.assertEqual(set(listxattr(fn)), xattr)
        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"")
        setxattr(fn, s("user.test"), b"hello", os.XATTR_REPLACE, **kwargs)
        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"hello")
        with self.assertRaises(OSError) as cm:
            setxattr(fn, s("user.test"), b"bye", os.XATTR_CREATE, **kwargs)
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        with self.assertRaises(OSError) as cm:
            setxattr(fn, s("user.test2"), b"bye", os.XATTR_REPLACE, **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        setxattr(fn, s("user.test2"), b"foo", os.XATTR_CREATE, **kwargs)
        xattr.add("user.test2")
        self.assertEqual(set(listxattr(fn)), xattr)
        removexattr(fn, s("user.test"), **kwargs)
        with self.assertRaises(OSError) as cm:
            getxattr(fn, s("user.test"), **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        xattr.remove("user.test")
        self.assertEqual(set(listxattr(fn)), xattr)
        self.assertEqual(getxattr(fn, s("user.test2"), **kwargs), b"foo")
        setxattr(fn, s("user.test"), b"a"*1024, **kwargs)
        self.assertEqual(getxattr(fn, s("user.test"), **kwargs), b"a"*1024)
        removexattr(fn, s("user.test"), **kwargs)
        many = sorted("user.test{}".format(i) for i in range(100))
        for thing in many:
            setxattr(fn, thing, b"x", **kwargs)
        self.assertEqual(set(listxattr(fn)), set(init_xattr) | set(many))
项目：rdiff-backup    作者：sol1    | 项目源码 | 文件源码 
def read_from_rp(self, rp):
        """Set the extended attributes from an rpath"""
        try:
            attr_list = rp.conn.xattr.listxattr(encode(rp.path),
                                                rp.issym())
        except IOError, exc:
            if exc[0] in (errno.EOPNOTSUPP, errno.EPERM, errno.ETXTBSY):
                return # if not supported, consider empty
            if exc[0] in (errno.EACCES, errno.ENOENT, errno.ELOOP):
                log.Log("Warning: listattr(%s): %s" % (repr(rp.path), exc), 4)
                return
            raise
        for attr in attr_list:
            if attr.startswith('system.'):
                # Do not preserve system extended attributes
                continue
            if not rp.isdir() and attr == 'com.apple.ResourceFork':
                # Resource Fork handled elsewhere, except for directories
                continue
            try:
                self.attr_dict[attr] = \
                    rp.conn.xattr.getxattr(encode(rp.path),
                                            attr, rp.issym())
            except IOError, exc:
                # File probably modified while reading, just continue
                if exc[0] == errno.ENODATA: continue
                elif exc[0] == errno.ENOENT: break
                # Handle bug in pyxattr < 0.2.2
                elif exc[0] == errno.ERANGE: continue
                else: raise
项目：kbe_server    作者：xiaohaoppy    | 项目源码 | 文件源码 
def _check_xattrs_str(self, s, getxattr, setxattr, removexattr, listxattr, **kwargs):
        fn = support.TESTFN
        open(fn, "wb").close()
        with self.assertRaises(OSError) as cm:
            getxattr(fn, s("user.test"), **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        init_xattr = listxattr(fn)
        self.assertIsInstance(init_xattr, list)
        setxattr(fn, s("user.test"), b"", **kwargs)
        xattr = set(init_xattr)
        xattr.add("user.test")
        self.assertEqual(set(listxattr(fn)), xattr)
        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"")
        setxattr(fn, s("user.test"), b"hello", os.XATTR_REPLACE, **kwargs)
        self.assertEqual(getxattr(fn, b"user.test", **kwargs), b"hello")
        with self.assertRaises(OSError) as cm:
            setxattr(fn, s("user.test"), b"bye", os.XATTR_CREATE, **kwargs)
        self.assertEqual(cm.exception.errno, errno.EEXIST)
        with self.assertRaises(OSError) as cm:
            setxattr(fn, s("user.test2"), b"bye", os.XATTR_REPLACE, **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        setxattr(fn, s("user.test2"), b"foo", os.XATTR_CREATE, **kwargs)
        xattr.add("user.test2")
        self.assertEqual(set(listxattr(fn)), xattr)
        removexattr(fn, s("user.test"), **kwargs)
        with self.assertRaises(OSError) as cm:
            getxattr(fn, s("user.test"), **kwargs)
        self.assertEqual(cm.exception.errno, errno.ENODATA)
        xattr.remove("user.test")
        self.assertEqual(set(listxattr(fn)), xattr)
        self.assertEqual(getxattr(fn, s("user.test2"), **kwargs), b"foo")
        setxattr(fn, s("user.test"), b"a"*1024, **kwargs)
        self.assertEqual(getxattr(fn, s("user.test"), **kwargs), b"a"*1024)
        removexattr(fn, s("user.test"), **kwargs)
        many = sorted("user.test{}".format(i) for i in range(100))
        for thing in many:
            setxattr(fn, thing, b"x", **kwargs)
        self.assertEqual(set(listxattr(fn)), set(init_xattr) | set(many))
项目：glustertool    作者：gluster    | 项目源码 | 文件源码 
def get_gfid(path):
    try:
        return uuid.UUID(bytes=xattr.get(path, "trusted.gfid",
                                         nofollow=True))
    except (IOError, OSError) as e:
        if e.errno == ENODATA:
            return uuid.UUID(bytes=xattr.get(path, "glusterfs.gfid",
                                             nofollow=True))
        else:
            raise
项目：obnam    作者：obnam-mirror    | 项目源码 | 文件源码 
def get_xattrs_as_blob(fs, filename):  # pragma: no cover
    tracing.trace('filename=%s' % filename)

    try:
        names = fs.llistxattr(filename)
    except (OSError, IOError), e:
        if e.errno in (errno.EOPNOTSUPP, errno.EACCES):
            return None
        raise
    tracing.trace('names=%s' % repr(names))
    if not names:
        return None

    values = []
    for name in names[:]:
        tracing.trace('trying name %s' % repr(name))
        try:
            value = fs.lgetxattr(filename, name)
        except OSError, e:
            # On btrfs, at least, this can happen: the filesystem returns
            # a list of attribute names, but then fails when looking up
            # the value for one or more of the names. We pretend that the
            # name was never returned in that case.
            #
            # Obviously this can happen due to race conditions as well.
            if e.errno == errno.ENODATA:
                names.remove(name)
                logging.warning(
                    '%s has extended attribute named %s without value, '
                    'ignoring attribute',
                    filename, name)
            else:
                raise
        else:
            tracing.trace('lgetxattr(%s)=%s' % (name, value))
            values.append(value)
    assert len(names) == len(values)

    name_blob = ''.join('%s\0' % name for name in names)

    lengths = [len(v) for v in values]
    fmt = '!' + 'Q' * len(values)
    value_blob = struct.pack(fmt, *lengths) + ''.join(values)

    return ('%s%s%s' %
            (struct.pack('!Q', len(name_blob)),
             name_blob,
             value_blob))
项目：glustertool    作者：gluster    | 项目源码 | 文件源码 
def run(args):
    # Volmark from Master side
    fmt_string = "!" + "B" * 19 + "II"
    try:
        vm = struct.unpack(fmt_string, xattr.get(
            args.path,
            "trusted.glusterfs.volume-mark",
            nofollow=True))
        print "UUID        : %s" % uuid.UUID(
            "".join(['%02x' % x for x in vm[2:18]]))
        print "VERSION     : %s.%s" % vm[0:2]
        print "RETVAL      : %s" % vm[18]
        print "VOLUME MARK : %s.%s (%s)" % (
            vm[19], vm[20], human_time("%s.%s" % (vm[19], vm[20])))
    except (OSError, IOError) as e:
        if e.errno == ENODATA:
            pass
        else:
            print "[Error %s] %s" % (e.errno, os.strerror(e.errno))
            sys.exit(-1)

    # Volmark from slave side
    all_xattrs = xattr.list(args.path)
    fmt_string = "!" + "B" * 19 + "II" + "I"
    volmark_xattrs = []
    for x in all_xattrs:
        if x.startswith("trusted.glusterfs.volume-mark."):
            volmark_xattrs.append(x)

    for vx in volmark_xattrs:
        try:
            vm = struct.unpack(fmt_string, xattr.get(
                args.path,
                vx))

            print "UUID        : %s" % uuid.UUID(
                "".join(['%02x' % x for x in vm[2:18]]))
            print "VERSION     : %s.%s" % vm[0:2]
            print "RETVAL      : %s" % vm[18]
            print "VOLUME MARK : %s.%s (%s)" % (
                vm[19], vm[20], human_time("%s.%s" % (vm[19], vm[20])))
            print "TIMEOUT     : %s (%s)" % (vm[-1], human_time(vm[-1]))
        except (OSError, IOError) as e:
            if e.errno == ENODATA:
                pass
            else:
                print "[Error %s] %s" % (e.errno, os.strerror(e.errno))
                sys.exit(-1)
项目：tm-librarian    作者：FabricAttachedMemory    | 项目源码 | 文件源码 
def getxattr(self, path, xattr, position=0):
        """Called with a specific namespace.name xattr.  Can return either
           a bytes array OR an int."""
        if position:
            raise TmfsOSError(errno.ENOSYS)    # never saw this in 8 months

        rsp = self.librarian(self.lcp('get_shelf', path=path))
        shelf = TMShelf(rsp)

        # Does this also need changed to support path instead of name?
        # Piggy back for queries by kernel (globals & fault handling).
        if xattr.startswith('_obtain_'):
            # this will need some work
            data = self.shadow.getxattr(shelf, xattr)
            try:
                return bytes(data.encode())
            except AttributeError as e:     # probably the "encode()"
                self._ret_is_string = False
                return bytes(data)

        # "ls" starts with simple getattr but then comes here for
        # security.selinux, system.posix_acl_access, and posix_acl_default.
        # ls -l can also do the same thing on '/'.  Save the round trips.

        # if xattr.startswith('security.') or not shelf_name:  # path == '/'
        if xattr.startswith('security.'):  # path == '/' is legal now
            return bytes(0)

        try:
            rsp = self.librarian(
                self.lcp('get_xattr', path=path, xattr=xattr))
            value = rsp['value']
            assert value is not None    # 'No such attribute'
            if isinstance(value, int):
                return value
            elif isinstance(value, str):
                # http://stackoverflow.com/questions/606191/convert-bytes-to-a-python-string
                return bytes(value.encode('cp437'))
            else:
                bytes(value.encode())
        except Exception as e:
            raise TmfsOSError(errno.ENODATA)    # syn for ENOATTR