如何解包msgpack文件？ [英] How to unpack a msgpack file?

问题描述

我写msgpack恩codeD数据到一个文件中。在写作，我只是使用C API的fbuffer。如（i条纹的所有错误处理的例子）：

I am writing msgpack-encoded data to a file. On writing, I am just using the fbuffer of the C API. As in (I striped all error handling for the example):

FILE *fp = fopen(filename, "ab");
msgpack_packer pk;
msgpack_packer_init(pk, fp, msgpack_fbuffer_write);
msgpack_pack_int(pk, 42);
// more data ...

我如何在读取此文件回来？我发现假设数据在内存中，但是，我的文件是否为5GB的所有例子中，它是不完全在内存完全持此一个好主意。此外，我不想读块我自己。毕竟，我不知道msgpack对象有多长，因此机会是我结束了我的缓冲半整数。

How do I read this file back in? All the example I found assume that the data is in memory, however, my files are up to 5GB, it is not exactly a good idea to hold this in memory completely. Also I do not want to read in chunks myself. After all, I do not know how long the msgpack objects are, so chances are I end up with half an integer in my buffer.

能否msgpack的解压不知何故从磁盘直接读取？或者是有一些标准的模式来做到这一点？

Can msgpack's unpack somehow read from disk directly? Or is there some standard pattern to do this?

推荐答案

您可能会考虑使用msgpack_unpacker为代替，这似乎是MessagePack实现了流式解串器的官方途径。看看msgpack-C /例子/ C / lib_buffer_unpack.c

You might consider using "msgpack_unpacker" for that instead, which seems to be the official way that MessagePack implements a 'streaming' deserializer. Have a look at msgpack-c/example/c/lib_buffer_unpack.c

问候，NiteHawk

Regards, NiteHawk

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