Hi, I'm new at the Forum, just I Hope to find some help here

I have some troubles when concatenating three char arrays. In fact, what I'm trying to do is the following:

Code:

int main(int argc, char** argv) {

                static char type[] = { 0x00,0x01,'\0'};      // I already tryied integers instead of hex values
		static char number_of_versions[] = {0x03,'\0'};
                static char versions[] = {0x04,0x05,'\0'};
                char *ptr;

                // When I print this the result is: 3 
                            
                
                // I tryied to allocate some memory as I want to save the result string in ptr.
                // See that I added +1 at the final for the \0 null terminated character of the string

               ptr = (char *)malloc(sizeof(type) + sizeof(number_of_versions)+sizeof(versions)+1);
                
              // Some printf to be sure that Im not missing anything. By the way, if I use strlen, 
              // the result is 0. Even if I inizialize string as {0,1,'\0'}.
               printf ("Sizeof Type %d, Sizeof number_of_versions %d, Sizeof versions %d \n",            
               sizeof(type),sizeof(number_of_versions),sizeof(versions));

                // To see what's in memory, even after some steps forwards.
                printf("Initial type[]  is:                 %x :   %x  :  %x \n",*type,*(type+1),*(type+2));
                printf("Initial ptr is:                     %X :   %X  :  %X : %X  :  %X :  %X  :  %X : %X  :  %X 
                \n",*ptr,*(ptr+1),*(ptr+2),*(ptr+3),*(ptr+4),*(ptr+5),*(ptr+6),*(ptr+7),*(ptr+8));
                printf("Initial N. of Versions:             %X :   %X  :  %X : %X  :  %X :  %X  :  %X : %X  :  %X 
                \n",*number_of_versions,*(number_of_versions+1),*(number_of_versions+2),*
                (number_of_versions+3),*(number_of_versions+4),*(number_of_versions+5),* 
                (number_of_versions+6),*(number_of_versions+7),*(number_of_versions+8));
               
               // I do ptr=type because if I try with strcpy, It will not take in account the string as the first 
               // element of type is 0 and it takes it as a NULL terminated character, so Its wrong :( 

               ptr = type;
                printf("After ptr=type, ptr is:          %X :   %X  :  %X : %X  :  %X :  %X  :  %X : %X  :  %X 
                \n",*ptr,*(ptr+1),*(ptr+2),*(ptr+3),*(ptr+4),*(ptr+5),*(ptr+6),*(ptr+7),*(ptr+8));
                
                // Now ptr is good, it is array 0,1 but when it concatenates it with number_of_versions,
                // it doesn't take in account the ptr string as the first value is zero, so same problem, 
               // and the result is just ptr = {3, '\0'} in place of {0,1,3,'\0'};

                strcat (ptr, number_of_versions);

                printf("After first concatenation ptr is:   %X :   %X  :  %X : %X  :  %X :  %X  :  %X : %X  :  
                %X \n",*ptr,*(ptr+1),*(ptr+2),*(ptr+3),*(ptr+4),*(ptr+5),*(ptr+6),*(ptr+7),*(ptr+8));
                printf("After first concatenation number_of_versions is: %X :   %X  :  %X : %X  :  %X :  
                %X  :  %X : %X  :  %X \n",*number_of_versions,*(number_of_versions+1),*
               (number_of_versions+2),*(number_of_versions+3),*(number_of_versions+4),*
               (number_of_versions+5),*(number_of_versions+6),*(number_of_versions+7),*
               (number_of_versions+8));
               
                // Finaly I want to concatenate this last string (versions),

                strcat (ptr, versions);

                printf("After second concatenation, ptr is:         %X :   %X  :  %X : %X  :  %X :  %X  :  %X : 
                 %X  :  %X:  %X  :  %X : %X  :  %X \n",*ptr,*(ptr+1),*(ptr+2),*(ptr+3),*(ptr+4),*(ptr+5),*
                (ptr+6),*(ptr+7),*(ptr+8),*(ptr+9),*(ptr+10),*(ptr+11),*(ptr+12));
                printf("The String Lenght of ptr is: %d", strlen(ptr));
               
               
                free(ptr);
                return 0;
                
 }

So, how Do I concatenate strings which contain zero values and do not represent it as zerro values as NULL characters?? Thank you!

I believe '\0' is the same as 0 which is the same as NULL.
In any case, just don't use strcat. You are not using valid characters, which are characters from 1-255 (0 is special for ending strings). Simply you cannot use 0 as a value for strings, only to end the string.
If you want to concate a string with 0-255 values then you have no ending character. Thus you will have to insert the length of the array on your homemade strcat

Yeah , I guess I should work with a complete string already...

I will try it this week and I will post what I found.

Cheers!