primitive data question

[ideru]

hello

too much use of CString and now I don't know how to use unsigned char anymore....

just some question/confirmation

unsigned char data[128];

1. how to put data? memcpy?
ex. memcpy(data, "the quick brown fox", 128 ) ---> ??

2. how to know the actual data length of the data variable??

[wildfrog]

Maybe this helps.

#include <memory.h>
#include <string.h>

unsigned char data[128];

int _tmain(int argc, _TCHAR* argv[])
{
    // using memcpy (be careful with the length, string length + ending zero)
    memcpy(data, "the quick brown fox", 20);

    // using strcpy (takes signed char*, not unsigned)
    strcpy((char*) data, "the quick brown fox");

    // using sprintf (takes signed char*, not unsigned)
    sprintf((char*) data, "the quick brown fox");

    // get size of data
    int datasize = sizeof(data);

    // get length of string contained within data (takes signed char*, not unsigned)
    int stringsize = strlen((char*) data);

    return 0;
}

- petter

[ideru]

thank you very much

[RoboTact]

hello

too much use of CString and now I don't know how to use unsigned char anymore....

just some question/confirmation

unsigned char data[128];

1. how to put data? memcpy?
ex. memcpy(data, "the quick brown fox", 128 ) ---> ??

2. how to know the actual data length of the data variable??

What is the context? What about that CString/unsigned char issue?

[kenrus]

2. how to know the actual data length of the data variable??

wildfrog's example is correct, but be careful of the common mistake ...

int EvalStr(char* data);

int main(int argc, char** argv)
{
     char data[128];

     EvalStr(data);

     return 0;
}

int EvalStr(char* data)
{
    int i = 0;

    i = sizeof(data);  /*returns sizeof char *, not allocated size of data*/

    strncpy(data, "My useful text information", i-1);

    return 0;
}

-Kendall