晋太元中,武陵人捕鱼为业。缘溪行,忘路之远近。忽逢桃花林,夹岸数百步,中无杂树,芳草鲜美,落英缤纷。渔人甚异之,复前行,欲穷其林。 林尽水源,便得一山,山有小口,仿佛若有光。便舍船,从口入。初极狭,才通人。复行数十步,豁然开朗。土地平旷,屋舍俨然,有良田、美池、桑竹之属。阡陌交通,鸡犬相闻。其中往来种作,男女衣着,悉如外人。黄发垂髫,并怡然自乐。 见渔人,乃大惊,问所从来。具答之。便要还家,设酒杀鸡作食。村中闻有此人,咸来问讯。自云先世避秦时乱,率妻子邑人来此绝境,不复出焉,遂与外人间隔。问今是何世,乃不知有汉,无论魏晋。此人一一为具言所闻,皆叹惋。余人各复延至其家,皆出酒食。停数日,辞去。此中人语云:“不足为外人道也。”(间隔 一作:隔绝) 既出,得其船,便扶向路,处处志之。及郡下,诣太守,说如此。太守即遣人随其往,寻向所志,遂迷,不复得路。 南阳刘子骥,高尚士也,闻之,欣然规往。未果,寻病终。后遂无问津者。
| DIR:/usr/include/linux/ |
| Current File : //usr/include/linux/watch_queue.h |
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _LINUX_WATCH_QUEUE_H
#define _LINUX_WATCH_QUEUE_H
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/ioctl.h>
#define O_NOTIFICATION_PIPE O_EXCL /* Parameter to pipe2() selecting notification pipe */
#define IOC_WATCH_QUEUE_SET_SIZE _IO('W', 0x60) /* Set the size in pages */
#define IOC_WATCH_QUEUE_SET_FILTER _IO('W', 0x61) /* Set the filter */
enum watch_notification_type {
WATCH_TYPE_META = 0, /* Special record */
WATCH_TYPE_KEY_NOTIFY = 1, /* Key change event notification */
WATCH_TYPE__NR = 2
};
enum watch_meta_notification_subtype {
WATCH_META_REMOVAL_NOTIFICATION = 0, /* Watched object was removed */
WATCH_META_LOSS_NOTIFICATION = 1, /* Data loss occurred */
};
/*
* Notification record header. This is aligned to 64-bits so that subclasses
* can contain __u64 fields.
*/
struct watch_notification {
__u32 type:24; /* enum watch_notification_type */
__u32 subtype:8; /* Type-specific subtype (filterable) */
__u32 info;
#define WATCH_INFO_LENGTH 0x0000007f /* Length of record */
#define WATCH_INFO_LENGTH__SHIFT 0
#define WATCH_INFO_ID 0x0000ff00 /* ID of watchpoint */
#define WATCH_INFO_ID__SHIFT 8
#define WATCH_INFO_TYPE_INFO 0xffff0000 /* Type-specific info */
#define WATCH_INFO_TYPE_INFO__SHIFT 16
#define WATCH_INFO_FLAG_0 0x00010000 /* Type-specific info, flag bit 0 */
#define WATCH_INFO_FLAG_1 0x00020000 /* ... */
#define WATCH_INFO_FLAG_2 0x00040000
#define WATCH_INFO_FLAG_3 0x00080000
#define WATCH_INFO_FLAG_4 0x00100000
#define WATCH_INFO_FLAG_5 0x00200000
#define WATCH_INFO_FLAG_6 0x00400000
#define WATCH_INFO_FLAG_7 0x00800000
};
/*
* Notification filtering rules (IOC_WATCH_QUEUE_SET_FILTER).
*/
struct watch_notification_type_filter {
__u32 type; /* Type to apply filter to */
__u32 info_filter; /* Filter on watch_notification::info */
__u32 info_mask; /* Mask of relevant bits in info_filter */
__u32 subtype_filter[8]; /* Bitmask of subtypes to filter on */
};
struct watch_notification_filter {
__u32 nr_filters; /* Number of filters */
__u32 __reserved; /* Must be 0 */
struct watch_notification_type_filter filters[];
};
/*
* Extended watch removal notification. This is used optionally if the type
* wants to indicate an identifier for the object being watched, if there is
* such. This can be distinguished by the length.
*
* type -> WATCH_TYPE_META
* subtype -> WATCH_META_REMOVAL_NOTIFICATION
*/
struct watch_notification_removal {
struct watch_notification watch;
__u64 id; /* Type-dependent identifier */
};
/*
* Type of key/keyring change notification.
*/
enum key_notification_subtype {
NOTIFY_KEY_INSTANTIATED = 0, /* Key was instantiated (aux is error code) */
NOTIFY_KEY_UPDATED = 1, /* Key was updated */
NOTIFY_KEY_LINKED = 2, /* Key (aux) was added to watched keyring */
NOTIFY_KEY_UNLINKED = 3, /* Key (aux) was removed from watched keyring */
NOTIFY_KEY_CLEARED = 4, /* Keyring was cleared */
NOTIFY_KEY_REVOKED = 5, /* Key was revoked */
NOTIFY_KEY_INVALIDATED = 6, /* Key was invalidated */
NOTIFY_KEY_SETATTR = 7, /* Key's attributes got changed */
};
/*
* Key/keyring notification record.
* - watch.type = WATCH_TYPE_KEY_NOTIFY
* - watch.subtype = enum key_notification_type
*/
struct key_notification {
struct watch_notification watch;
__u32 key_id; /* The key/keyring affected */
__u32 aux; /* Per-type auxiliary data */
};
#endif /* _LINUX_WATCH_QUEUE_H */
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