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+HIREDIS OVERVIEW
+----------------
+
+Hiredis is a minimalistic C client library for the Redis Database.
+
+It is minimalistic because it just adds minimal support for the protocol, but
+at the same time it uses an high level printf-alike API in order to make it
+much higher level than otherwise suggested by its minimal code base and the
+lack of explicit bindings for every Redis command.
+
+Hiredis only supports the new Redis protocol, so you can use it with any
+Redis version >= 1.2.0.
+
+HIREDIS API
+-----------
+
+Hiredis exports only three function calls:
+
+ redisReply *redisConnect(int *fd, char *ip, int port);
+ redisReply *redisCommand(int fd, char *format, ...);
+ void freeReplyObject(redisReply *r);
+
+The first function is used in order to create a connection to the Redis server:
+
+ redisReply *reply;
+ int fd;
+
+ reply = redisConnect(&fd,"127.0.0.1",6379);
+
+to test for connection errors all it is needed to do is checking if reply
+is not NULL:
+
+ if (reply != NULL) {
+ printf("Connection error: %s\n", reply->reply);
+ freeReplyObject(reply);
+ exit(1);
+ }
+
+When a reply object returns an error, the reply->type is set to the value
+`REDIS_REPLY_ERROR`, and reply->reply points to a C string with the description
+of the error.
+
+In the above example we don't check for reply->type as `redisConnect()` can
+only return `NULL` or a reply object that is actually an error.
+
+As you can see `redisConnect()` will just set (by reference) the `fd` variable
+to the file descriptor of the open socket connected to our Redis server.
+
+Calls to `redisCommand()` will require this file descriptor as first argument.
+
+SENDING COMMANDS
+----------------
+
+Commands are sent using a printf-alike format. In the simplest form it is
+like that:
+
+ reply = redisCommand("SET foo bar");
+
+But you can use "%s" and "%b" format specifiers to create commands in a
+printf-alike fashion:
+
+ reply = redisComand("SET foo %s", somevalue);
+
+If your arguments are binary safe, you can use "%b" that receives the pointer
+to the buffer and a size_t integer with the length of the buffer.
+
+ reply = redisCommand("SET %s %b", "foo", somevalue, somevalue_length);
+
+Internally Hiredis will split the command in different arguments and will
+convert it to the actual protocol used to communicate with Redis.
+Every space will separate arguments, so you can use interpolation.
+The following example is valid:
+
+ reply = redisCommand("SET key:%s %s", myid, value);
+
+USING REPLIES
+-------------
+
+`redisCommand()` returns a reply object. In order to use this object you
+need to test the reply->type field, that can be one of the following types:
+
+* `REDIS_REPLY_ERROR`:
+ The command returned an error string, that can be read accessing to
+ the reply->reply field.
+
+* `REDIS_REPLY_STRING`:
+ The command returned a string, that can be read accessing to the
+ reply->reply field. The string is always null-terminated, but when you
+ need to work with binary-safe strings you can obtain the exact length
+ of the reply with: `sdslen(reply->reply)`.
+
+* `REDIS_REPLY_ARRAY`:
+ The command returned an array of reply->elements elements.
+ Every element is a redisReply object, stored at redis->element[..index..]
+ Redis may reply with nested arrays but this is fully supported.
+
+* `REDIS_REPLY_INTEGER`:
+ The command replies with an integer. It's possible to access this integer
+ using the reply->integer field that is of type "long long".
+
+* `REDIS_REPLY_NIL`:
+ The command replies with a NIL special object. There is no data to access.
+
+FREEING REPLIES
+---------------
+
+Replies should be freed using the `freeReplyObject()` function.
+Note that this function will take care of freeing sub-replies objects
+contained in arrays and nested arrays, so there is no need for the user to
+free the sub replies (it is actually harmful and will corrupt the memory).
+
+AUHTOR
+------
+
+Hiredis was written by Salvatore Sanfilippo (antirez at gmail) and is
+released under the BSD license.