Thread: Query on accessing and assigning (unsigned char *) to int32_t

Hi All,

I have a following code .

Code:

      1 #include <stdio.h>
      2 #include <stdint.h>
      3
      4 struct temp
      5 {
      6     char sa_data[10];
      7
      8 };
      9
     10 int main()
     11 {
     12     unsigned char *c;
     13     struct temp test;
     14     static int32_t var;
     15
     16     c = &test.sa_data[0];
     17
     18     test.sa_data[0] = 0xAB;
     19     var = c[0];
     20
     21     printf("%x %x \n",c[0],var);
     22
     23     return 0;
     24 }

Two queries here are.

1. At line number 16, we are assigning address of sa_data[0] to unsigned char and while printing we are not using '*' , how it can still print the value of the variable instead address..?

2. when i am trying to assign int32_t data type variable with unsigned char pointer ,why it does not throw any type cast warning in compilation?.

Thanks in advance.

Thanks salem,

One more query on subject int32_t . I have two machines with different gcc versions.

When i include this data type in my program and try to compile i see that it depends on stdio.h in one and stdlib.h in another.

Here with gcc version gcc version 4.4.7 20120313 (Red Hat 4.4.7-17) (GCC) , i see that its getting included from stdlib.h .

Where as with gcc (SUSE Linux) 4.3.4 [gcc-4_3-branch revision 152973] , its getting included from stdio.h.

By any chance do you know like , Is this observation correct?. I was testing by commenting the header files and seeing the compilation errors.

Thanks in advance.