K&R C and strings

[pkirk25]

I wonder if anyone has time to write a small example program based on
this data or to critique my own effort?

A file called Realm List.html contains the following data:
Bladefist-Horde
Nordrassil-Horde
Draenor-Alliance
Nordrassil-Alliance
Nordrassil-Neutral
Draenor-Horde
Moonglade-Horde
Shadowmoon-Horde
Moonglade-Alliance

I need an algorithm that takes from this list the names of Realms that
we have both Alliance and Horde data for and to list them in
alphabetical order. My desired format of this list will be:
Draenor-Alliance
Draenor-Horde
Moonglade-Alliance
Moonglade-Horde
Nordrassil-Alliance
Nordrassil-Horde

I'm committed to using ANSI C with the K&R book as my guide. It says a
string is an array of chars.

Right now I can open the file, I can use strtok to split each line but
I can't work out how to create an array of these strings?

FILE *realmList;
if((realmList=f open("Realm List.html","w+" )) == NULL)
{
printf("Couldn' t open \"Realm List.html\" for output\n");
return 1;
}

/*
List Realms and count of each
*/
char strLine[244];

while (fgets(strLine, 244, realmList))
{

char *tmp = NULL;
char token[] = "-";
tmp = strtok(strLine, token);

printf("%s\n", tmp);
/* stuck at this point */
}

[CBFalconer]

Richard Heathfield wrote:

we******@gmail. com said:

.... snip ...

>>
I am not in charge of the www or your access to it. I can get
the bstring.sf.net without difficulty. You can try
bstring.source forge.net which is the same thing.

That worked. The compilation didn't, though. You're a bit cavalier
with constness.

websnarl has also been known to assume 32 bit integers and 8 bit
chars.

--
Some informative links:
<news:news.anno unce.newusers
<http://www.geocities.c om/nnqweb/>
<http://www.catb.org/~esr/faqs/smart-questions.html>
<http://www.caliburn.nl/topposting.html >
<http://www.netmeister. org/news/learn2quote.htm l>
<http://cfaj.freeshell. org/google/>

[Richard Heathfield]

CBFalconer said:

Richard Heathfield wrote:

>we******@gmail. com said:

... snip ...

>>>
I am not in charge of the www or your access to it. I can get
the bstring.sf.net without difficulty. You can try
bstring.sourc eforge.net which is the same thing.

That worked. The compilation didn't, though. You're a bit cavalier
with constness.

websnarl has also been known to assume 32 bit integers and 8 bit
chars.

That's a tempting assumption to make at times. But I can find no definitive
evidence of either assumption in bstrlib (after a very cursory inspection).

I would consider it reasonable to make the 8-bit char assumption provided
that the code checks that the assumption is true and fails to compile if it
is false (#if CHAR_BIT 8 / #error ...), and provided that the reasons for
the assumption are made clear, and provided that guidance is given on what
areas would need looking at if someone were to attempt to remove the
dependence on that assumption.

For example, there are times when you'd sure like to have an array with one
element for each possible unsigned char value. (Boyer-Moore springs to
mind.) If CHAR_BIT is 8, this involves a mere 256 * sizeof(type) bytes. If
CHAR_BIT is 16, however, the overhead becomes significant. And if it's 32,
well... even if it's just an array of unsigned char, you're still talking
16 Gigoctets, which is very significant indeed!

I can see no plausible necessity for assuming that integers have 32 bits,
however. But I stress again that I have seen no definitive evidence that Mr
Websnarf has assumed this. Despite the plethora of 32s in the code, there
are significant indications that he is aware of the fact that integers need
not have 32 bits.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)

[websnarf]

Richard Heathfield wrote:

we******@gmail. com said:

Richard Heathfield wrote:

we******@gmail. com said:
In straight C strings are just a rats nest of pain and suffering.

For websnarf, this may well be true. Other people seem to manage, though.

Yes, you can see evidence of this through CERT's advisory list or even
the lists from Secunia. So others "manage" alright -- they *manage* to
write code that doesn't work.

Um, so what? The existence of people who cannot understand C does not imply
the non-existence of people who can.

But you have not provided any evidence of people who can, outside an
assertion. Where's your solution to the OP's problem? Surely such a
trivial question couldn't pose more effort than it took for you to
write the drivel you've posted in this thread so far.

It's possible using the ordinary C string library too.

We know its *possible*. But the fact that nobody has posted such a
thing is probably evidence of something.

It could just be evidence of DYOH.

<snip>

Every question on c.l.c could be a DYOH question. But this one is easy
to recognize as not being a homework question. Because its really easy
to solve in any other language or using Bstrlib, and is a really
serious pain in the ass to solve in C -- but at the same time there are
really very few fundamental *concepts* being taught in an exercise like
this. The only value of this exercise, to solve in C, is to learn what
a really horridly useless language C is when dealing with strings and
ADTs in general, which most institutions would not bother spending an
exercise on.

Its interesting how you see things so narrowly: there *could* be
programmers that can use the standard libraries string functions
perfectly, therefore that *must* be the right way to do things. Any
question *could* be a homework question, therefore it *is* a homework
question. You know the battery in your computer? It *could* explode;
you better stop using it.

I have written a
string library called "The Better String Library" which is perfectly
suited for this.

Of the two URLs in your sig, one failed to load at all, and the other
presented a bizarre set of cartoon drawings, none of which had any
obvious relation to any kind of string libraries.

I am not in charge of the www or your access to it. I can get the
bstring.sf.net without difficulty. You can try bstring.sourcef orge.net
which is the same thing.

That worked. The compilation didn't, though. You're a bit cavalier with
constness.

Well I didn't check it, but I highly doubt that "const" is my problem.
Looking at it again, it could be that some compiler is annoyed by my
coercion of void * to bstring. It should be a warning at most though.

--
Paul Hsieh
http://www.pobox.com/~qed/
http://bstring.sf.net/

[Richard Heathfield]

we******@gmail. com said:

Richard Heathfield wrote:

>we******@gmail. com said:

Richard Heathfield wrote:
we******@gmail. com said:
In straight C strings are just a rats nest of pain and suffering.

For websnarf, this may well be true. Other people seem to manage,
though.

Yes, you can see evidence of this through CERT's advisory list or even
the lists from Secunia. So others "manage" alright -- they *manage* to
write code that doesn't work.

Um, so what? The existence of people who cannot understand C does not
imply the non-existence of people who can.

But you have not provided any evidence of people who can, outside an
assertion.

Is it your claim that no such people exist? I offer as obvious
counter-examples the following (non-exhaustive!) list: Dennis Ritchie,
Brian Kernighan, Doug Gwyn, Nick Maclaren, Chris Torek, Lawrence Kirby, Dan
Pop, Chris Dollin, Ben Pfaff, Dann Corbit, Peter Seebach, Clive Feather,
Greg Comeau, and P J Plauger. None of these would have the slightest
problem sorting an array of strings.

Where's your solution to the OP's problem?

I chose not to write one. I am under no obligation to write one. Yes, I
could have provided an example that used my own string library, much as you
did with yours. But that would, IMHO, not have been in keeping with the
OP's request for an ANSI C solution, which suggested to me that he didn't
want a canned response involving a large library. (I accept that I could be
mistaken about that.)

Or I could have coded one up from scratch. I doubt whether there are many
people here (other than, perhaps, yourself) who would question my ability
to do that. It is, after all, a simple enough exercise. Populate the array,
and call qsort. Easy.

Surely such a
trivial question couldn't pose more effort than it took for you to
write the drivel you've posted in this thread so far.

If it's such drivel, why respond to it?

>It's possible using the ordinary C string library too.

We know its *possible*. But the fact that nobody has posted such a
thing is probably evidence of something.

It could just be evidence of DYOH.

<snip>

Every question on c.l.c could be a DYOH question.

Indeed.

But this one is easy to recognize as not being a homework question.

I think not.

Because its really easy
to solve in any other language or using Bstrlib, and is a really
serious pain in the ass to solve in C

....but Bstrlib is written in C! Sheesh, get a life.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)

[Michael Mair]

Richard Heathfield schrieb:

we******@gmail. com said:

>>pkirk25 wrote:

<snip>

>>>I need an algorithm that takes from this list the names of Realms that
we have both Alliance and Horde data for and to list them in
alphabetic al order. My desired format of this list will be:
Draenor-Alliance
Draenor-Horde
Moonglade-Alliance
Moonglade-Horde
Nordrassil-Alliance
Nordrassil-Horde

So you want to sort the lines of text alphabetically right?

>>>I'm committed to using ANSI C with the K&R book as my guide. It says a
string is an array of chars.

Close. It's a sequence of adjacent characters (typically stored in an array,
yes) that is terminated by the first null character in that sequence.

>>In straight C strings are just a rats nest of pain and suffering.

For websnarf, this may well be true. Other people seem to manage, though.

I _can_ do many things, including reinventing the (polygonal) wheel time
and again. (ISO) C, in my opinion, is not the language to use if you
heavily operate on / with strings and want results quickly.

<snip>

>>By using more advanced strings (i.e., not the crap that the language
comes with),

Not everyone shares websnarf's opinion.

>>this is possible in the C language.

It's possible using the ordinary C string library too.

Yes, it is.
As I wrote in my response to the OP, <4n************ @individual.net >,
C IMO is not the "best" or "easiest" language for this task.
As long as the OP does not suffer through this for learning purposes,
I see no point in restricting oneself to standard C.
I do not care at all for websnarf's acerbic to poisonous tone and
unobjective colouring of his assessments, though.

>>I have written a
string library called "The Better String Library" which is perfectly
suited for this.

<snipped by Richard: Code using bstrlib>

The code looks sufficiently clear, I'd still rather use Perl or python.
Cheers
Michael
--
E-Mail: Mine is an /at/ gmx /dot/ de address.

[websnarf]

Richard Heathfield wrote:

we******@gmail. com said:

Richard Heathfield wrote:

we******@gmail. com said:
Richard Heathfield wrote:
we******@gmail. com said:
In straight C strings are just a rats nest of pain and suffering.

For websnarf, this may well be true. Other people seem to manage,
though.

Yes, you can see evidence of this through CERT's advisory list or even
the lists from Secunia. So others "manage" alright -- they *manage* to
write code that doesn't work.

Um, so what? The existence of people who cannot understand C does not
imply the non-existence of people who can.

But you have not provided any evidence of people who can, outside an
assertion.

Is it your claim that no such people exist?

No, I claim that you have not provided any evidence. Think of it from
the OP's point of view. Suppose he has a question in his mind about
whether or not its even possible to solve the problem in C. How would
you convince him that it was possible? (Well you could always point
him to my post ...)

[...] I offer as obvious
counter-examples the following (non-exhaustive!) list: Dennis Ritchie,
Brian Kernighan, Doug Gwyn, Nick Maclaren, Chris Torek, Lawrence Kirby, Dan
Pop, Chris Dollin, Ben Pfaff, Dann Corbit, Peter Seebach, Clive Feather,
Greg Comeau, and P J Plauger. None of these would have the slightest
problem sorting an array of strings.

Uh ... probably so; I'd even be willing to bet CBFalconer could do it,
but its interesting that you should go to such an "illustriou s list"
for such ridiculously simple problem -- and yet at the same time, still
provide no solution to the problem at hand.

(BTW, I think you have to remove Peter Seebach from that list. I've
seen some of his more marvellous efforts -- programming is not his
strong suit. Assuming you've fixed your internet go check this out:
http://www.seebs.net/ops/ibm/email/sz.c and the sz.h file. Its like
the MS3K of C programming; its so bad its good.)

Where's your solution to the OP's problem?

I chose not to write one. I am under no obligation to write one. Yes, I
could have provided an example that used my own string library, much as you
did with yours. But that would, IMHO, not have been in keeping with the
OP's request for an ANSI C solution,

Uhh... just trying to untangle that logic -- you are saying you have
your own C library for strings that you use that isn't ANSI compliant?

[...] which suggested to me that he didn't
want a canned response involving a large library.

Well that's interesting -- I just don't follow your reasoning at all.
Is there something in the ANSI C language standard that says large
libraries are disallowed?

(I accept that I could be mistaken about that.)

Yathink?

Or I could have coded one up from scratch. I doubt whether there are many
people here (other than, perhaps, yourself) who would question my ability
to do that.

I question the effort required.

[...] It is, after all, a simple enough exercise. Populate the array,
and call qsort. Easy.

Oh yeah, real easy. So easy, you're not even going to do it.

Surely such a
trivial question couldn't pose more effort than it took for you to
write the drivel you've posted in this thread so far.

If it's such drivel, why respond to it?

Because it required no effort? (You're not following along are you?)

It's possible using the ordinary C string library too.

We know its *possible*. But the fact that nobody has posted such a
thing is probably evidence of something.

It could just be evidence of DYOH.

<snip>

Every question on c.l.c could be a DYOH question.

Indeed.

But this one is easy to recognize as not being a homework question.

I think not.

I'm sure Warcraft is really important subject matter for that class
he's taking.

Because its really easy
to solve in any other language or using Bstrlib, and is a really
serious pain in the ass to solve in C

...but Bstrlib is written in C! Sheesh, get a life.

So did you ever take a course in formal logic? I mean seriously,
what's your problem? You know Bstrlib has been written over a period
of several years and I've received lots of feedback on improving it (so
technically some changes and ideas were technically beyond my
thinking/experience). So if I could argue, for a second, that Bstrlib
was a pain in the ass to write, then what exactly is your problem?

--
Paul Hsieh
http://www.pobox.com/~qed/
http://bstring.sf.net/

[Keith Thompson]

Richard Heathfield <in*****@invali d.invalidwrites :

we******@gmail. com said:

[...]

>I am not in charge of the www or your access to it. I can get the
bstring.sf.n et without difficulty. You can try bstring.sourcef orge.net
which is the same thing.

That worked. The compilation didn't, though. You're a bit cavalier with
constness.

Really? It compiled for me with no diagnostics.

I used:

gcc -ansi -pedantic -W -Wall -O3 -c bstrlib.c

using gcc versions 2.7.2.2, 3.4.4, and 4.0.2.

--
Keith Thompson (The_Other_Keit h) ks***@mib.org <http://www.ghoti.net/~kst>
San Diego Supercomputer Center <* <http://users.sdsc.edu/~kst>
We must do something. This is something. Therefore, we must do this.

[Richard Heathfield]

Keith Thompson said:

Richard Heathfield <in*****@invali d.invalidwrites :

>we******@gmail. com said:

[...]

>>I am not in charge of the www or your access to it. I can get the
bstring.sf.ne t without difficulty. You can try bstring.sourcef orge.net
which is the same thing.

That worked. The compilation didn't, though. You're a bit cavalier with
constness.

Really?

Yes.

It compiled for me with no diagnostics.

I used:

gcc -ansi -pedantic -W -Wall -O3 -c bstrlib.c

using gcc versions 2.7.2.2, 3.4.4, and 4.0.2.

FYI, I used -W -Wall -ansi -pedantic -Wformat-nonliteral -Wcast-align
-Wpointer-arith -Wbad-function-cast -Wmissing-prototypes
-Wstrict-prototypes -Wmissing-declarations -Winline -Wundef
-Wnested-externs -Wcast-qual -Wshadow -Wconversion -Wwrite-strings
-Wno-conversion -ffloat-store -O2 with gcc 2.95.3.

--
Richard Heathfield
"Usenet is a strange place" - dmr 29/7/1999
http://www.cpax.org.uk
email: rjh at above domain (but drop the www, obviously)

[pkirk25]

Its always interesting to come back to a newsgroup and see a thread
that has taken on a life of its own.

Fond though I am of World of Warcraft, my project is mainly about
learning C.

Why C instead of C# or Java?

Once upon a time i was a programmer in VB6. I will never touch any
language that is the plaything of a vendor. I still use MSAccess VBA
for projects and find myself wondering why MS decided to kill VB for
those of us who regard OOP as a distraction.

I know from hiring C++ developers that it takes 2 years full time work
experience in C++ to become productive. Even then, C++ developers seem
to have semi-religous practices that require them to abuse other C++
developers. Worse, when one leaves, the "better" his coding standards,
the less likely you are to hire someone who can understand his
object-orientated aspect-guided paradigm-style code and you have to pay
for the whole lot to be done again! So for my hobby project to
automating World of Warcraft gold trading, C++ may well be a better
tool but I don't have 2 full years to devote to any hobby.

C is small - you can learn it it a few weeks - I started last Thursday
and already have something that is usable. Almost every evening, when
I start to code, I watch the damn thing crash. But that feeling of
being able to make it work and my it work ANY which way you choose is
why I chose C. If I wanted to do things the "right" way, I'd be a VB
..NET junkie waiting for MS to decide that VB. NET is a dead end.

I post this in the hope that those who have become very heated about
how best to help me will feel a little better about my bumbling efforts
at reinventing the wheel again and again.

Patrick

[Mabden]

"pkirk25" <pa*****@kirks. netwrote in message
news:11******** *************@d 34g2000cwd.goog legroups.com...

Two great answers.

Thanks - if I can make it all fit together I may well become the first
World of Warcraft gold millionaire!

Add:

And p.s. You will get nothing for writing it for me!

--
Mabden