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CocoaAsyncSocket and socket read data

On my server based on a TCP socket, I send packets downstream, where the packets consist of a header indicating the number of bytes in the packet, followed by this number of bytes. For those familiar with Erlang, I just set the {package, 4} parameter. On the iOS side, I have a code that looks like this if I want to find out the stream size for this post:

[asyncSocket readDataToLength:4 withTimeout:-1 tag:HEADER_TAG];

This works fine, and the following delegate method callback is called:

onSocket:didReadData:withTag:

I believe the next logical step is to determine the size of the stream, and I do this with

  UInt32 readLength;
  [data getBytes:&readLength length:4];
  readLength = ntohl(readLength);

After hard-coding a string of 12 bytes on the server side, readLength really reads 12 on the client, so for now, everything is fine. I continue with the following:

 [sock readDataToLength:readLength withTimeout:1 tag:MESSAGE_TAG];

, onSocket:didReadData:withTag: . - , , - , , :

- (NSTimeInterval)onSocket:(AsyncSocket *)sock shouldTimeoutReadWithTag:(long)tag elapsed:(NSTimeInterval)elapsed bytesDone:(NSUInteger)length

16 , 4 12- .

, , CocoaAsyncSocket. , ?

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, , . , readDataToLength . :

[socket readDataWithTimeout:-1 tag:HEADER_TAG];

:

- (void)onSocket:(AsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag {
    if (tag == HEADER_TAG) {
        UInt32 readLength;
        [data getBytes:&readLength length:4];
        readLength = ntohl(readLength);
        int offset = 4;
        NSRange range = NSMakeRange(offset, readLength);
        char buffer[readLength];
        [data getBytes:&buffer range:range];
        NSLog(@"buffer %s", buffer);
        //[sock readDataToLength:readLength withTimeout:1 tag:MESSAGE_TAG];
    } else if (tag == MESSAGE_TAG) {
        //[sock readDataToLength:4 withTimeout:1 tag:HEADER_TAG];
    }

}

, , . , , Erlang {, 4}. , . , readDataToLength? , ?

+5
1

, Erlang, . {packet, 4} 4- . Erlang ( 4, , 2 Gb). Erlang inet:setopts/2.

, - , . , . , readDataToLength .

+1

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