(part 5) Dick Heathfield's book errors

[Borked Pseudo Mailed]

Richard Heathfield said:

>>Mick Charles Beaver said:

>Hello,

>Would anyone know why the FreeBSD implementation of swab() uses an
unsigned long for its temporary variable when swapping bytes?

<snip>

although those casts are a bit pointless, aren't they?

From swab.c:

void
swab(const void * __restrict from, void * __restrict to, ssize_t len)
{
unsigned long temp;
int n;
char *fp, *tp;

n = len >1;
fp = (char *)from;
tp = (char *)to;

From Dick Heathfield's _C Unleashed_ Random() function
on pg. 406:

int Random(int n)
{
double d;

d = rand() / (RAND_MAX + 1.0);
d *= n;

return (int)d;
}

[H&S 9.8: "If a function has a declared return type T
that is not void, then the type of any expression appearing
in a return statement must be convertible to type T by
assignment, and that conversion in fact happens on return
in both Standard and traditional C.

Example
In a function with declared return type int, the
statement
return 23.1;
is equivalent to
return (int) 23.1;
which is the same as
return 23
"]

That cast in Random() is a bit pointless, isn't it? Any
defense about style or lint-like programs could equally
apply to the unnecessary casts in swab.c.

Yours,
Han from China

"It is likely that Schildt knows what a linked list is, and
it's even likely that he explains it well. What is
somewhat less likely is that his implementation is
robust." -- Richard Heathfield, 2000

[John Bode]

On Oct 29, 2:35*pm, Borked Pseudo Mailed <[e-mail]>
wrote:

[snip]

From Dick Heathfield's _C Unleashed_ Random() function
on pg. 406:

int Random(int n)
{
* double d;

* d = rand() / (RAND_MAX + 1.0);
* d *= n;

* return (int)d;

}

[H&S 9.8: "If a function has a declared return type T
that is not void, then the type of any expression appearing
in a return statement must be convertible to type T by
assignment, and that conversion in fact happens on return
in both Standard and traditional C.

Example
* In a function with declared return type int, the
statement
* * *return 23.1;
is equivalent to
* * return (int) 23.1;
which is the same as
* * return 23
"]

That cast in Random() is a bit pointless, isn't it? Any
defense about style or lint-like programs could equally
apply to the unnecessary casts in swab.c.

Yours,
Han from China

"It is likely that Schildt knows what a linked list is, and
it's even likely that he explains it well. What is
somewhat less likely is that his implementation is
robust." -- Richard Heathfield, 2000

I can't believe I'm taking the time to respond to this trolling
jackass, but...

You *do* realize that Heathfield wasn't the only author of that book?
That he's just one of, what, 8 or 9 authors?

Again, why does Richard get all the anti-groupies, as opposed to Ben,
Steve, Keith, Eric, etc.?

[Eric Sosman]

John Bode wrote:

[...]
Again, why does Richard get all the anti-groupies, as opposed to Ben,
Steve, Keith, Eric, etc.?

Perhaps because Richard (as he has explained) is reluctant to
use the killfile. Can't speak for the others, but my killfile is
threatening to outgrow the SAN ...

--
Er*********@sun.com

[Peter Nilsson]

John Bode <[e-mail]:

Borked Pseudo Mailed <[e-mail]:
[snip]

Let's put it back...
Richard Heathfield said: [in another thread]
although those casts are a bit pointless, aren't they?

..._C Unleashed_ Random() function on pg. 406:
int Random(int n)
...
* return (int)d;

I can't believe I'm taking the time to respond to this
trolling jackass,

Even a 'trolling jackass' can ask valid questions. [I
guess I'm proof of that. ;-] Of course, I don't support
the motives or unconstructive manner in which 'Han from
China' asks them.

but...

You *do* realize that Heathfield wasn't the only author
of that book? That he's just one of, what, 8 or 9
authors?

True, but 7 or 8 of those 8 or 9 only appear as 'et al'
on the front cover. I believe Lawrence was the main proof
reader, however that only makes the question more valid.
[Though not necessarily interesting.]

--
Peter

[Antoninus Twink]

On 29 Oct 2008 at 20:29, John Bode wrote:

Again, why does Richard get all the anti-groupies, as opposed to Ben,
Steve, Keith, Eric, etc.?

Perhaps because while those other people can sometimes be unhelpful,
irritating, pedantic ninnies, only Heathfield is a megalomaniac?

[Jack Klein]

On Wed, 29 Oct 2008 13:29:33 -0700 (PDT), John Bode
<jf********@gmail.comwrote in comp.lang.c:

On Oct 29, 2:35*pm, Borked Pseudo Mailed <[e-mail]>
wrote:

[snip]

From Dick Heathfield's _C Unleashed_ Random() function
on pg. 406:

int Random(int n)
{
* double d;

* d = rand() / (RAND_MAX + 1.0);
* d *= n;

* return (int)d;

}

[H&S 9.8: "If a function has a declared return type T
that is not void, then the type of any expression appearing
in a return statement must be convertible to type T by
assignment, and that conversion in fact happens on return
in both Standard and traditional C.

Example
* In a function with declared return type int, the
statement
* * *return 23.1;
is equivalent to
* * return (int) 23.1;
which is the same as
* * return 23
"]

That cast in Random() is a bit pointless, isn't it? Any
defense about style or lint-like programs could equally
apply to the unnecessary casts in swab.c.

Yours,
Han from China

"It is likely that Schildt knows what a linked list is, and
it's even likely that he explains it well. What is
somewhat less likely is that his implementation is
robust." -- Richard Heathfield, 2000

I can't believe I'm taking the time to respond to this trolling
jackass, but...

You *do* realize that Heathfield wasn't the only author of that book?
That he's just one of, what, 8 or 9 authors?

Again, why does Richard get all the anti-groupies, as opposed to Ben,
Steve, Keith, Eric, etc.?

I agree, I'm starting to feel neglected.

Surely there's _something_ wrong with Chapter 18?

--
Jack Klein
Home: http://JK-Technology.Com
FAQs for
comp.lang.c http://c-faq.com/
comp.lang.c++ http://www.parashift.com/c++-faq-lite/
alt.comp.lang.learn.c-c++
http://www.club.cc.cmu.edu/~ajo/docs/FAQ-acllc.html

[Richard Heathfield]

Peter Nilsson said:

<snip>

Even a 'trolling jackass' can ask valid questions. [I
guess I'm proof of that. ;-] Of course, I don't support
the motives or unconstructive manner in which 'Han from
China' asks them.

Neither do I, which is why I'm not answering them.

<snip>

I believe Lawrence was the main proof
reader, however that only makes the question more valid.
[Though not necessarily interesting.]

It's not a terribly interesting question. It is, however, a valid question.
The answer, however, is no - Lawrence wasn't the main proofreader. If he
had been, it would have been an even better book (but on the other hand,
we were already riding roughshod over deadlines as it was).

--
Richard Heathfield <http://www.cpax.org.uk>
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999

[Richard Heathfield]

Jack Klein said:

<snip>

>
Surely there's _something_ wrong with Chapter 18?

There are 29 reported errata, most being minor typographical errors.

Some of the errata were reported by a Mr J Klein. :-)

--
Richard Heathfield <http://www.cpax.org.uk>
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999

[user923005]

On Oct 30, 5:32*am, Richard Heathfield <[e-mail]:

Peter Nilsson said:

<snip>

Even a 'trolling jackass' can ask valid questions. [I
guess I'm proof of that. ;-] Of course, I don't support
the motives or unconstructive manner in which 'Han from
China' asks them.

Neither do I, which is why I'm not answering them.

<snip>

I believe Lawrence was the main proof
reader, however that only makes the question more valid.
[Though not necessarily interesting.]

It's not a terribly interesting question. It is, however, a valid question.
The answer, however, is no - Lawrence wasn't the main proofreader. If he
had been, it would have been an even better book (but on the other hand,
we were already riding roughshod over deadlines as it was).

I had two proof readers for chapter 13.
One proofreader was an employee of the book company.
The second proofreader was...
Peter Seebach!
Maybe he was looking for IAQ entries.
;-)