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libmemcached_examples.pop

libmemcached_examples.pop

Section: libmemcached_examples (3) Updated: 2010-01-07
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NAME

libmemcached_examples - Examples for libmemcached  

DESCRIPTION

For full examples, test cases are found in tests/*.c in the main distribution. These are always up to date, and are used for each test run of the library.  

Creating and Freeing structure

  memcached_st *memc;
  memcached_return_t rc;

  memc= memcached_create(NULL);
  ...do stuff...
  memcached_free(memc);

The above code would create a connection and then free the connection when finished.  

Connecting to servers

  memcached_server_st *servers;
  memcached_st *memc= memcached_create(NULL);
  char servername[]= "0.example.com";

  servers= memcached_server_list_append(NULL, servername, 400, &rc);

  for (x= 0; x < 20; x++)
  {
    char buffer[SMALL_STRING_LEN];

    snprintf(buffer, SMALL_STRING_LEN, "%u.example.com", 400+x);
    servers= memcached_server_list_append(servers, buffer, 401, &rc);
  }
  rc= memcached_server_push(memc, servers);
  memcached_server_free(servers);
  memcached_free(memc);

In the above code you create a "memcached_st" object that you then feed in a single host into. In the for loop you build a "memcached_server_st" pointer that you then later feed via memcached_server_push() into the "memcached_st" structure.

You can reuse the "memcached_server_st" object with multile "memcached_st" structures.  

Adding a value to the server

  char *key= "foo";
  char *value;
  size_t value_length= 8191;
  unsigned int x;

  value = (char*)malloc(value_length);
  assert(value);

  for (x= 0; x < value_length; x++)
  value[x] = (char) (x % 127);

  for (x= 0; x < 1; x++)
  {
    rc= memcached_set(memc, key, strlen(key), 
    value, value_length,
    (time_t)0, (uint32_t)0);
    assert(rc == MEMCACHED_SUCCESS);
  }

  free(value);

It is best practice to always look at the return value of any operation.  

Fetching multiple values

  memcached_return_t rc;
  char *keys[]= {"fudge", "son", "food"};
  size_t key_length[]= {5, 3, 4};
  unsigned int x;
  uint32_t flags;

  char return_key[MEMCACHED_MAX_KEY];
  size_t return_key_length;
  char *return_value;
  size_t return_value_length;

  rc= memcached_mget(memc, keys, key_length, 3);

  x= 0;
  while ((return_value= memcached_fetch(memc, return_key, &return_key_length, 
                                        &return_value_length, &flags, &rc)))
  {
    free(return_value);
    x++;
  }

Notice that you freed values returned from memcached_fetch(). The define "MEMCACHED_MAX_KEY" is provided for usage.  

HOME

To find out more information please check: <https://launchpad.net/libmemcached>  

AUTHOR

Brian Aker, <brian@tangent.org>  

SEE ALSO

memcached(1)


 

Index

NAME
DESCRIPTION
Creating and Freeing structure
Connecting to servers
Adding a value to the server
Fetching multiple values
HOME
AUTHOR
SEE ALSO

This document was created by man2html, using the manual pages.
Time: 21:49:19 GMT, April 16, 2011