Name

lcb_unlock — unlock a document

Synopsis

cc [ flag … ] file… -lcouchbase [ library … ]

#include <libcouchbase/couchbase.h>
lcb_error_t lcb_unlock(lcb_t instance,
                       const void *command_cookie,
                       lcb_size_t num,
                       const lcb_unlock_cmd_t *const *commands);

DESCRIPTION

lcb_unlock() is used to unlock a document previously locked with lcb_get(). If the library instance is using asynchronous mode (the default) this operation will return immediately and schedule the operations to be executed by the event loop, otherwise it will block until all commands are executed. command_cookie is is an opaque field that will be provided to the callback function. num is the number of entries in the commands array.

lcb_unlock_cmd_t is a structure defined in <libcouchbase/arguments.h>:

typedef struct lcb_unlock_cmd_st {
    int version;              /* The enty in "v" to use */
    union {
        struct {
            const void *key;    /* The key this response belongs to */
            lcb_size_t nkey;    /* The number of bytes in the key */
            lcb_cas_t cas;      /* The lock identified */
            const void *hashkey; /* hash key if != key */
            lcb_size_t nhashkey; /* number of bytes in hash key */
        } v0;
    } v;
} lcb_unlock_cmd_t;

Please note that using the another key for hashing may lead to an unbalanced cluster if the key does not distribute well with a crc32 hashing function.

Upon completion the unlock callback as set by lcb_set_unlock_callback is called.

RETURN VALUES

lcb_unlock() returns the LCB_SUCCESS on success, or a specific error code upon failure. See lcb_strerror(3couchbase) for more information.

EXAMPLES

#include <libcouchbase/couchbase.h>
...
lcb_t instance;
...
lcb_unlock_cmd_t *unlock = calloc(1, sizeof(*unlock));
unlock->version = 0;
unlock->v.v0.key = "my-key";
unlock->v.v0.nkey = strlen(unlock->v.v0.key);
unlock->v.v0.cas = 0x666;
lcb_unlock_cmd_t* commands[] = { unlock };
lcb_unlock(instance, NULL, 1, commands);
...

ATTRIBUTES

See lcb_attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE

Interface Stability

Committed

MT-Level

MT-Safe

COPYRIGHT

Copyright 2010-2013 Couchbase, Inc.

SEE ALSO

Learn more at http://www.couchbase.com/communities/c.

libcouchbase(3lib), lcb_get_unlock_callback(3couchbase), lcb_set_unlock_callback(3couchbase), lcb_attributes(5)