c++ - Passing the Number of Elements in an Array to Function? -

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i writing dll passes char array function. define char array 22 elements here:

unsigned char data[22] = { 0x00, 0x0a, 0x00, 0x09, 0x70, 0x00, 0x72, 0x00,  0x6f, 0x00, 0x74, 0x00, 0x68, 0x00, 0x65, 0x00, 0x67, 0x00, 0x75, 0x00, 0x79, 0x00 };

now, try pass array function declared as:

bool senddata(unsigned char* sdata, unsigned long ssize);

with these arguments: 

senddata(data, 22);

this code compiles, crashes program when function called. taking closer while debugging, can see there's access violation in function senddata. looking further, see values of data , sdata @ run-time:

  1. data points 22 byte char array correct values (obviously)
  2. sdata points char array null-terminated first byte, containing 1 value (0)

it clear me compiler not know allocate 22 bytes sdata, because not specify length it. question is:

how specify length of sdata argument passed won't terminate early?

if i'm wrong issue, please correct me , explain further. in advance!

edit:

i understand \0 (the first byte , many more in data) null-terminator , prematurely end array. asking how avoid this. understanding sdata never given specific length , therefore stops on \0, may wrong.

i asked supply senddata function:

bool senddata(unsigned char* sdata, unsigned long ssize) {     try     {         send(sdata, ssize);         return true;     } catch (...)     {     return false;     } }

send calling function module, isn't relevant issue, error occurs beforehand when sdata argument passed senddata.

no allocation of sdata going happen, points array. displays empty in debugger because displays char* string, , strings end when there '/0', first byte. not mean sdata not have correct data. write sdata[0]. sdata[1], etc, in debugger see correct values.


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