13 Aug
2006
13 Aug
'06
8:53 p.m.
It was thus said that the Great Don once stated:
Ethan Dicks wrote:
No, they aren't. But I personally never remembered if C stores arrays row
major, or column major. Then again, I rarely use two dimentional arrays
anyway.
But really, it gets to me when I see code like:
for (i = 0 ; i < MAX ; i++)
foo[i] = 0;
when it could easily be replaced with:
memset(foo,0,sizeof(foo));
(which would work on multiple dimentioned arrays) or, if C allowed it:
foo = 0;
(to me, if the compiled sees array rvalue being set to a single lvalue,
then the intent I want as a programmer is to set the entire array to that
single value).
The "real" problem was that the first guy didn't really understand the
impact of his original construction on the underlying system, and "it
worked" for a few thousand names. Didn't scale worth beans, though.
Exactly. Like:
for (x=0; x<XMAX; x++)
for (y=0; y<YMAX; y++)
foo[x][y] = ...;
vs.
for (y=0; y<YMAX; y++)
for (x=0; x<XMAX; x++)
foo[x][y] = ...;
They *look* the same but *aren't*. I found one piece of code that was literally counting
bytes
to determine the size of a file instead of stat(2)-ing it
(no, it wasn't a sparse file, special device, etc. ... just
a regular "box of bytes")
That's just the programmer not knowing the available functions, or
perhaps, coming from a system that doesn't have stat() available (it's not
part of the ANSI-C standard library, limiting the ways one can get the size
of a file portably, and each of them having problems). For more horror
stories, you can always check out http://thedailywtf.com/ .
-spc (Have compiler, will program)