git.m6w6.name Git - awesomized/libmemcached/blob - docs/source/libmemcached/memcached_servers.rst

   1 Managing the servers used by memcached_st
   2 =========================================
   3
   4 SYNOPSIS
   5 --------
   6
   7 #include <libmemcached/memcached.h>
   8     Compile and link with -lmemcached
   9
  10 .. function:: uint32_t memcached_server_count (memcached_st *ptr)
  11
  12     :param ptr: pointer to initialized `memcached_st` struct
  13     :returns: number of configured servers
  14
  15 .. function:: memcached_return_t memcached_server_add (memcached_st *ptr, const char *hostname, in_port_t port)
  16
  17     :param ptr: pointer to initialized `memcached_st` struct
  18     :param hostname: hostname or IP address of the TCP server to add
  19     :param port: port of the TCP server
  20     :returns: `memcached_return_t` indicating success
  21
  22 .. function:: memcached_return_t memcached_server_add_udp (memcached_st *ptr, const char *hostname, in_port_t port)
  23
  24     :param ptr: pointer to initialized `memcached_st` struct
  25     :param hostname: hostname or IP address of the UDP server to add
  26     :param port: port of the UDP server
  27     :returns: `memcached_return_t` indicating success
  28
  29 .. function:: memcached_return_t memcached_server_add_unix_socket (memcached_st *ptr, const char *socket)
  30
  31     :param ptr: pointer to initialized `memcached_st` struct
  32     :param socket: path to the UNIX socket of the server to add
  33     :returns: `memcached_return_t` indicating success
  34
  35 .. function:: memcached_return_t memcached_server_push (memcached_st *ptr, const memcached_server_st *list)
  36
  37     :param ptr: pointer to initialized `memcached_st` struct
  38     :param list: pre-configured list of servers to push
  39     :returns: `memcached_return_t` indicating success
  40
  41 .. function:: const memcached_instance_st * memcached_server_by_key (memcached_st *ptr, const char *key, size_t key_length, memcached_return_t *error)
  42
  43     :param ptr: pointer to initialized `memcached_st` struct
  44     :param key: key to hash and lookup a server
  45     :param key_length: length of `key` without any terminating zero
  46     :param error: pointer to `memcached_return_t` indicating success
  47     :returns: the server instance to be used for storing/retrieving `key`
  48
  49 .. function:: const memcached_instance_st * memcached_server_get_last_disconnect (const memcached_st *ptr)
  50
  51     :param ptr: pointer to initialized `memcached_st` struct
  52     :returns: the instance of the last server for which there was a connection problem
  53
  54 .. function:: memcached_return_t memcached_server_cursor(const memcached_st *ptr, const memcached_server_fn *callback, void *context, uint32_t number_of_callbacks)
  55
  56     :param ptr: pointer to initialized `memcached_st` struct
  57     :param callback: list of `memcached_server_fn` to be called for each server instance
  58     :param context: pointer to user supplied context for the callback
  59     :param number_of_callbacks: number of callbacks supplied
  60     :returns: `memcached_return_t` indicating success
  61
  62 .. type:: memcached_return_t (*memcached_server_fn)(const memcached_st *ptr, const memcached_instance_st * server, void *context)
  63
  64     :param ptr: pointer to the `memcached_st` struct
  65     :param server: pointer to `memcached_instance_st`
  66     :param context: pointer to user supplied context
  67     :returns: `memcached_return_t` indicating success
  68
  69 DESCRIPTION
  70 -----------
  71
  72 `libmemcached` performs operations on a list of hosts. The order of
  73 these hosts determine routing to keys. Functions are provided to add keys to
  74 `memcached_st` structures. To manipulate lists of servers see
  75 `memcached_server_st`.
  76
  77 :func:`memcached_server_count` provides you a count of the current number of
  78 servers being used by a :type:`memcached_st` structure.
  79
  80 :func:`memcached_server_add` pushes a single TCP server into the
  81 :type:`memcached_st` structure. This server will be placed at the end.
  82 Duplicate servers are allowed, so duplication is not checked. Executing this
  83 function with the `MEMCACHED_BEHAVIOR_USE_UDP` behavior set will result in
  84 a `MEMCACHED_INVALID_HOST_PROTOCOL`.
  85
  86 :func:`memcached_server_add_udp` pushes a single UDP server into the
  87 :type:`memcached_st` structure. This server will be placed at the end. Duplicate
  88 servers are allowed, so duplication is not checked. Executing this function
  89 without setting the `MEMCACHED_BEHAVIOR_USE_UDP` behavior will result in a
  90 `MEMCACHED_INVALID_HOST_PROTOCOL`.
  91
  92 :func:`memcached_server_add_unix_socket` pushes a single UNIX socket into the
  93 :type:`memcached_st` structure. This UNIX socket will be placed at the end.
  94 Duplicate servers are allowed, so duplication is not checked. The length
  95 of the filename must be one character less than `MEMCACHED_MAX_HOST_LENGTH`.
  96
  97 :func:`memcached_server_push` pushes an array of :type:`memcached_server_st`
  98 into the :type:`memcached_st` structure. These servers will be placed at
  99 the end. Duplicate servers are allowed, so duplication is not checked. A
 100 copy is made of structure so the list provided (and any operations on
 101 the list) are not saved.
 102
 103 :func:`memcached_server_by_key` allows you to provide a key and retrieve the
 104 server which would be used for assignment.
 105
 106 :func:`memcached_server_get_last_disconnect` returns a pointer to the last
 107 server for which there was a connection problem. It does not mean this
 108 particular server is currently dead but if the library is reporting a server
 109 is, the returned server is a very good candidate.
 110
 111 :func:`memcached_server_cursor` takes a memcached_st and loops through the
 112 list of hosts currently in the cursor calling the list of callback
 113 functions provided. You can optionally pass in a value via
 114 context which will be provided to each callback function. An error
 115 return from any callback will terminate the loop.
 116 :func:`memcached_server_cursor` is passed the original caller
 117 :type:`memcached_st` in its current state.
 118
 119 RETURN VALUE
 120 ------------
 121
 122 Varies, see particular functions.
 123
 124 SEE ALSO
 125 --------
 126
 127 .. only:: man
 128
 129     :manpage:`memcached(1)`
 130     :manpage:`libmemcached(3)`
 131     :manpage:`memcached_server_st(3)`
 132     :manpage:`memcached_strerror(3)`
 133
 134 .. only:: html
 135
 136     * :manpage:`memcached(1)`
 137     * :doc:`../libmemcached`
 138     * :doc:`memcached_server_st`
 139     * :doc:`memcached_strerror`