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 UWA week 36 (2nd semester, mid-semester break) ↓
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1:03pm Tue 6th Sep, Haoxuan L.

char *strcpy_pointer( char *dest, char *src ) // two pointer parameters { char *origdest = dest; // take a copy of the dest parameter while( *src != '\0' ) { *dest = *src; // copy one character from src to dest ++src; ++dest; } *dest = '\0'; return origdest; // returns copy of original destination parameter } why do we need a *origdest variable? Can't we just return *dest?


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7:20am Wed 7th Sep, Christopher M.

"Haoxuan Long" <23*4*1*[email protected]*u*e*t*u*a*e*u*a*> wrote:
> why do we need a *origdest variable? Can't we just return *dest?
This example has followed the way the standard strcpy() function works. While C doesn't have a basic string datatype, we can't copy strings with string2 = string1; So strcpy() is written so that we can read it the same way - strcpy(string2, string1); Then, the result of the function is (the start of) string2, so that we can write: printf("result is %s\n", strcpy(string2, string1) ); or strcpy(string3, strcpy(string2, string1) ); analogous to: string3 = string2 = string1; There would be little point returning the value of dest in the provided implementation, as it's a pointer which always points to a null-byte, and we have no way of knowing which string that actually relates to.

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