The `CLIENT LIST` command returns information and statistics about the client
connections server in a mostly human readable format.

You can use one of the optional subcommands to filter the list. The `TYPE type`
subcommand filters the list by clients' type, where _type_ is one of `normal`,
`master`, `replica`, and `pubsub`. Note that clients blocked by the `MONITOR`
command belong to the `normal` class.

The `ID` filter only returns entries for clients with IDs matching the
`client-id` arguments.

@return

@bulk-string-reply: a unique string, formatted as follows:

- One client connection per line (separated by LF)
- Each line is composed of a succession of `property=value` fields separated by
  a space character.

Here is the meaning of the fields:

- `id`: an unique 64-bit client ID.
- `name`: the name set by the client with `CLIENT SETNAME`
- `addr`: address/port of the client
- `laddr`: address/port of local address client connected to (bind address)
- `fd`: file descriptor corresponding to the socket
- `age`: total duration of the connection in seconds
- `idle`: idle time of the connection in seconds
- `flags`: client flags (see below)
- `db`: current database ID
- `sub`: number of channel subscriptions
- `psub`: number of pattern matching subscriptions
- `multi`: number of commands in a MULTI/EXEC context
- `qbuf`: query buffer length (0 means no query pending)
- `qbuf-free`: free space of the query buffer (0 means the buffer is full)
- `obl`: output buffer length
- `oll`: output list length (replies are queued in this list when the buffer is
  full)
- `omem`: output buffer memory usage
- `events`: file descriptor events (see below)
- `cmd`: last command played
- `argv-mem`: incomplete arguments for the next command (already extracted from
  query buffer)
- `tot-mem`: total memory consumed by this client in its various buffers
- `redir`: client id of current client tracking redirection
- `user`: the authenticated username of the client

The client flags can be a combination of:

```
A: connection to be closed ASAP
b: the client is waiting in a blocking operation
c: connection to be closed after writing entire reply
d: a watched keys has been modified - EXEC will fail
i: the client is waiting for a VM I/O (deprecated)
M: the client is a master
N: no specific flag set
O: the client is a client in MONITOR mode
P: the client is a Pub/Sub subscriber
r: the client is in readonly mode against a cluster node
S: the client is a replica node connection to this instance
u: the client is unblocked
U: the client is connected via a Unix domain socket
x: the client is in a MULTI/EXEC context
t: the client enabled keys tracking in order to perform client side caching
R: the client tracking target client is invalid
B: the client enabled broadcast tracking mode
```

The file descriptor events can be:

```
r: the client socket is readable (event loop)
w: the client socket is writable (event loop)
```

## Notes

New fields are regularly added for debugging purpose. Some could be removed in
the future. A version safe Redis client using this command should parse the
output accordingly (i.e. handling gracefully missing fields, skipping unknown
fields).

@history

- `>= 2.8.12`: Added unique client `id` field.
- `>= 5.0`: Added optional `TYPE` filter.
- `>= 6.2`: Added `laddr` field and the optional `ID` filter.