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If you like, you can write another simple function, company_name,
that returns a pointer to the portion of the description that contains the
company-identifying characters.
Because the company name occupies the final portion of the description string, there is no need to create a new character array. Instead, you can view the final portion of the description string as a substring.
Thus, the company_name function can do its job by locating the
character in the description string immediately following the hyphen,
whereupon the company_name function can return the address of that
character. That address is the address of a substring containing the
company-identifying characters. In the following, for example,
company_name is to return 922:
description
*--------*--------*
|00000011|10011000|
*--------*--------*
-----------------
|
*-------*
|
| C - I B M Null character
| | | | | | |
v v v v v v v
-------- -------- -------- -------- -------- --------
----*--------*--------*--------*--------*--------*--------*-
|01000011|00101101|01001001|01000010|01001101|00000000|
---*--------*--------*--------*--------*--------*--------*---
920 921 922 923 924 925
The following is one interesting way to implement company_name.
Note that nothing needs to be initialized in the for statement; hence,
nothing appears before the first semicolon. Also note that the iteration
terminates when the cptr pointer points to the hyphen; hence, the
pointer has to be incremented once after leaving the for loop so as
to move the pointer forward to the first character in the company name:
char* company_name (struct trade *t) {
char* cptr = t -> for;
description (; cptr[0] != '-'; ++cptr) ;
return ++cptr;
}