Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.c > #55136 > unrolled thread

Pascal style string in C language

Back to article view | Back to comp.lang.c

Contents

  Pascal style string in C language Dejan Grubesic <dejangru@gmail.com> - 2014-12-20 03:31 -0800
    Re: Pascal style string in C language BartC <bc@freeuk.com> - 2014-12-20 11:44 +0000
      Re: Pascal style string in C language Geoff <geoff@invalid.invalid> - 2014-12-20 09:09 -0800
        Re: Pascal style string in C language Geoff <geoff@invalid.invalid> - 2014-12-20 09:20 -0800
    Re: Pascal style string in C language Siri Crews <chine.bleu@yahoo.com> - 2014-12-20 04:02 -0800
    Re: Pascal style string in C language Dejan Grubesic <dejangru@gmail.com> - 2014-12-20 04:25 -0800
      Re: Pascal style string in C language Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-20 12:10 -0800
    Re: Pascal style string in C language Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-20 16:40 +0100
      Re: Pascal style string in C language Dexterr <dejangru@gmail.com> - 2014-12-21 03:07 -0800
        Re: Pascal style string in C language raltbos@xs4all.nl (Richard Bos) - 2014-12-21 17:50 +0000
    Re: Pascal style string in C language Keith Thompson <kst-u@mib.org> - 2014-12-20 12:08 -0800
      Re: Pascal style string in C language Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-20 12:13 -0800
        Re: Pascal style string in C language Keith Thompson <kst-u@mib.org> - 2014-12-20 12:50 -0800
          Re: Pascal style string in C language Dexterr <dejangru@gmail.com> - 2014-12-21 03:09 -0800
            Re: Pascal style string in C language James Kuyper <jameskuyper@verizon.net> - 2014-12-21 09:56 -0500
              Re: Pascal style string in C language gazelle@shell.xmission.com (Kenny McCormack) - 2014-12-21 15:52 +0000
                Re: Pascal style string in C language Dexterr <dejangru@gmail.com> - 2014-12-21 08:01 -0800
                  Re: Pascal style string in C language glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-12-22 00:40 +0000
                  Re: Pascal style string in C language Richard Damon <Richard@Damon-Family.org> - 2014-12-22 11:49 -0500
                Re: Pascal style string in C language Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-21 17:55 +0100
                  Re: Pascal style string in C language Dexterr <dejangru@gmail.com> - 2014-12-22 05:45 -0800
                    Re: Pascal style string in C language gazelle@shell.xmission.com (Kenny McCormack) - 2014-12-22 14:40 +0000
                  Re: Pascal style string in C language gazelle@shell.xmission.com (Kenny McCormack) - 2015-01-09 20:32 +0000
                    Re: Pascal style string in C language gazelle@shell.xmission.com (Kenny McCormack) - 2015-01-09 20:33 +0000
                Re: Pascal style string in C language Öö Tiib <ootiib@hot.ee> - 2014-12-21 14:36 -0800
                  Re: Pascal style string in C language Dexterr <dejangru@gmail.com> - 2014-12-21 15:06 -0800
                Re: Pascal style string in C language glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2014-12-22 00:38 +0000
                Re: Pascal style string in C language Tim Rentsch <txr@alumni.caltech.edu> - 2014-12-23 00:06 -0800
      Re: Pascal style string in C language Dexterr <dejangru@gmail.com> - 2014-12-21 03:06 -0800
    Re: Pascal style string in C language Les Cargill <lcargill99@comcast.com> - 2014-12-20 14:27 -0600

Page 1 of 2  [1] 2  Next page →

#55136 — Pascal style string in C language

Hi there,

please I need a help. How you can write one Pascal style string in C language but as a structure ?

Could someone write a function in C with two strings, one in C style and other in Pascal style and compare it. If its true function return true, when not false.

Regards.

[toc] | [next] | [standalone]

#55137

On 20/12/2014 11:31, Dejan Grubesic wrote:

> please I need a help. How you can write one Pascal style string in C language but as a structure ?

What does a Pascal style string look like?

-- 
Bartc

[toc] | [prev] | [next] | [standalone]

#55152

On Sat, 20 Dec 2014 11:44:48 +0000, BartC <bc@freeuk.com> wrote:

>On 20/12/2014 11:31, Dejan Grubesic wrote:
>
>> please I need a help. How you can write one Pascal style string in C language but as a structure ?
>
>What does a Pascal style string look like?

It's an array of char of size 256 and the first char is the length of
the string it contains. 

struct pascal_string {
	unsigned char length;
	char *string;
};

[toc] | [prev] | [next] | [standalone]

#55153

On Sat, 20 Dec 2014 09:09:01 -0800, Geoff <geoff@invalid.invalid>
wrote:

>On Sat, 20 Dec 2014 11:44:48 +0000, BartC <bc@freeuk.com> wrote:
>
>>On 20/12/2014 11:31, Dejan Grubesic wrote:
>>
>>> please I need a help. How you can write one Pascal style string in C language but as a structure ?
>>
>>What does a Pascal style string look like?
>
>It's an array of char of size 256 and the first char is the length of
>the string it contains. 
>
>struct pascal_string {
>	unsigned char length;
>	char *string;
>};

Correction:

struct pascal_string {
	unsigned char length;
	char string[255];
};

[toc] | [prev] | [next] | [standalone]

#55139

In article <7d8fd4fa-43f2-4caa-abe6-31d60113c7a7@googlegroups.com>,
 Dejan Grubesic <dejangru@gmail.com> wrote:

> Hi there,
> 
> please I need a help. How you can write one Pascal style string in C language 
> but as a structure ?
> 
> Could someone write a function in C with two strings, one in C style and 
> other in Pascal style and compare it. If its true function return true, when 
> not false.

The usual way has a 255 byte limit with the length stored in the first byte.

    char cstring[100] = "...";
    char pstring[100];
        *((unsigned char)pstring) = strlen(cstring);
        memcpy(pstring+1, cstring, *((unsigned char)pstring));

You can extend that by using multiple initial bytes for the length.


To use a struct, you're going to have make a decision of a maxiumum length string

    struct {size_t length; char string[maximumlength];}

a dynamically allocated string

    struct {size_t length; char *string;}

or a string that slops over the struct;

    typedef struct {size_t length; char string[1];} String1, *PString;
    #define String(N) struct {String1 header; char trailer[(N)-1];}

-- 
:-<> Siri Seal of Disavowal #000-001. Disavowed. Denied. Deleted.
'I desire mercy, not sacrifice.'
Icke's razor: Given two equally plausible explanations, choose the weirder.
Be sure not to operate heavy machinery whilst on usenet.

[toc] | [prev] | [next] | [standalone]

#55140

On Saturday, December 20, 2014 12:31:30 PM UTC+1, Dejan Grubesic wrote:
> Hi there,
> 
> please I need a help. How you can write one Pascal style string in C language but as a structure ?
> 
> Could someone write a function in C with two strings, one in C style and other in Pascal style and compare it. If its true function return true, when not false.
> 
> Regards.

Is this OK ?

// Mississippi

typedef America {
  char us_state[25];
};

America pascal_string = {11, 'M', 'i', 's', 's', 'i', 's', 's', 'i', 'p' , 'p', 'i'}; 

America pascal_string = "\11" "Mississippi";
America pascal_string = "\x11Mississippi";

[toc] | [prev] | [next] | [standalone]

#55168

On Saturday, December 20, 2014 12:25:48 PM UTC, Dexterr wrote:
> 
> Is this OK ?
> 
> // Mississippi
> 
> typedef America {
>   char us_state[25];
> };
> 
> America pascal_string = {11, 'M', 'i', 's', 's', 'i', 's', 's', 'i', 'p' , 'p', 'i'}; 
> 
> America pascal_string = "\11" "Mississippi";
> America pascal_string = "\x11Mississippi";
>
So it's easy enough, if a bit fiddly.

int compareCandpascal(char *pascal, char *c)
{
   int pascal_len;
   int i;

   pascal_len = (unsigned char)pascal[0];
   for(i=0;i<pascal_len;i++)
   {
      if(c[i] == 0)
         return -1;
      if(c[i] != pascal[i+1])
         return (c[i] > pascal[i+1]) ? 1 : -1;
   }
   if(c[i] != 0)
     return 1;
   return 0;
}

The only thing that is special about C strings is that a string literal
creates one. You can pass strings about as Pascal strings in C if you
know that they will never go above 255 characters, and you write your
own library routines to handle them.

[toc] | [prev] | [next] | [standalone]

#55149

Il 20/12/2014 12:31, Dejan Grubesic ha scritto:

> [..] How you can write one Pascal style string in C language but as a structure ?
>
> Could someone write a function in C with two strings, one in C style and other in Pascal style and compare it. If its true function return true, when not false.
..

May I ask you what do you need that for?

-- 
Vincenzo Mercuri

[toc] | [prev] | [next] | [standalone]

#55176

On Saturday, December 20, 2014 4:40:07 PM UTC+1, Vincenzo Mercuri wrote:
> Il 20/12/2014 12:31, Dejan Grubesic ha scritto:
> 
> > [..] How you can write one Pascal style string in C language but as a structure ?
> >
> > Could someone write a function in C with two strings, one in C style and other in Pascal style and compare it. If its true function return true, when not false.
> ..
> 
> May I ask you what do you need that for?
> 
> -- 
> Vincenzo Mercuri

I am learning C Programming.

[toc] | [prev] | [next] | [standalone]

#55217

Dexterr <dejangru@gmail.com> wrote:

> On Saturday, December 20, 2014 4:40:07 PM UTC+1, Vincenzo Mercuri wrote:
> > Il 20/12/2014 12:31, Dejan Grubesic ha scritto:
> > 
> > > [..] How you can write one Pascal style string in C language but as a structure ?
> > 
> > May I ask you what do you need that for?
> 
> I am learning C Programming.

Then don't do this. One can't learn C by recreating Pascal, any more
than one can't learn English by recreating Latin (Victorian split
infinitive pedantry notwithstanding).

Instead, focus on writing programs that use C strings correctly.

Richard

[toc] | [prev] | [next] | [standalone]

#55166

Dejan Grubesic <dejangru@gmail.com> writes:
> please I need a help. How you can write one Pascal style string in C
> language but as a structure ?
>
> Could someone write a function in C with two strings, one in C style
> and other in Pascal style and compare it. If its true function return
> true, when not false.

Yes, I could, with an assumption or two about what your problem
statement actually means.

This looks very much like a homework assignment.  If you're asking us to
do your homework for you, please provide your instructor's e-mail
address so we can submit our solutions directly.  Of course we'll
mention your name.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

[toc] | [prev] | [next] | [standalone]

#55169

On Saturday, December 20, 2014 8:08:17 PM UTC, Keith Thompson wrote:
> 
> This looks very much like a homework assignment.  If you're asking us to
> do your homework for you, please provide your instructor's e-mail
> address so we can submit our solutions directly.  Of course we'll
> mention your name.
> 
Interfacing C to Pascal or other languages is a common but non-homeworky
requirement. I hadn't considered that it was a homework task.

[toc] | [prev] | [next] | [standalone]

#55172

Malcolm McLean <malcolm.mclean5@btinternet.com> writes:
> On Saturday, December 20, 2014 8:08:17 PM UTC, Keith Thompson wrote:
>> This looks very much like a homework assignment.  If you're asking us to
>> do your homework for you, please provide your instructor's e-mail
>> address so we can submit our solutions directly.  Of course we'll
>> mention your name.
>> 
> Interfacing C to Pascal or other languages is a common but non-homeworky
> requirement. I hadn't considered that it was a homework task.

Perhaps (which is why I wrote "If").  But the question shows no effort
by the OP to solve it himself, and the very narrow requirement to write
a function to compare a C-style string vs. a Pascal-string smells to me
like homework.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

[toc] | [prev] | [next] | [standalone]

#55177

On Saturday, December 20, 2014 9:51:07 PM UTC+1, Keith Thompson wrote:
> Malcolm McLean <malcolm.mclean5@btinternet.com> writes:
> > On Saturday, December 20, 2014 8:08:17 PM UTC, Keith Thompson wrote:
> >> This looks very much like a homework assignment.  If you're asking us to
> >> do your homework for you, please provide your instructor's e-mail
> >> address so we can submit our solutions directly.  Of course we'll
> >> mention your name.
> >> 
> > Interfacing C to Pascal or other languages is a common but non-homeworky
> > requirement. I hadn't considered that it was a homework task.
> 
> Perhaps (which is why I wrote "If").  But the question shows no effort
> by the OP to solve it himself, and the very narrow requirement to write
> a function to compare a C-style string vs. a Pascal-string smells to me
> like homework.
> 
> -- 
> Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
> Working, but not speaking, for JetHead Development, Inc.
> "We must do something.  This is something.  Therefore, we must do this."
>     -- Antony Jay and Jonathan Lynn, "Yes Minister"

If you have some problem with homework just avoid this post. I don't need your fucking suggestion!

[toc] | [prev] | [next] | [standalone]

#55199

On 12/21/2014 06:09 AM, Dexterr wrote:
> On Saturday, December 20, 2014 9:51:07 PM UTC+1, Keith Thompson wrote:
...
>> Perhaps (which is why I wrote "If").  But the question shows no effort
>> by the OP to solve it himself, and the very narrow requirement to write
>> a function to compare a C-style string vs. a Pascal-string smells to me
>> like homework.
>>
>> -- 
>> Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
>> Working, but not speaking, for JetHead Development, Inc.
>> "We must do something.  This is something.  Therefore, we must do this."
>>     -- Antony Jay and Jonathan Lynn, "Yes Minister"
> 
> If you have some problem with homework just avoid this post. I don't need your fucking suggestion!

The problem is not with homework, but with people who get homework
assignments and ask for help without having apparently even attempted to
solve it themselves. And that's just as much of a problem even if you're
teaching yourself rather than being taught by someone else.
-- 
James Kuyper

[toc] | [prev] | [next] | [standalone]

#55202

In article <m76n2k$8d2$1@dont-email.me>,
James Kuyper  <jameskuyper@verizon.net> wrote:
...
>The problem is not with homework, but with people who get homework
>assignments and ask for help without having apparently even attempted to
>solve it themselves. And that's just as much of a problem even if you're
>teaching yourself rather than being taught by someone else.

That may be the intent, but in practice, you have to ask yourself why it is
that if someone hits the same problem in their dead-end job and posts about
it here (without, apparently, having done any work themselves), then
somehow that is OK.

The over-arching point is that homework problems are exactly the kinds of
problems that CLC is setup to handle.  We should be encouraging it, not
discouraging it.  The reason is this:

    1) Homework problems are likely to be simple to solve, likely to be
	solvable using so-called "standard C", don't involve anything hinkey
	or real-world useable (i.e., tend to be abstractions of real-world
	problems) - and in general don't involve any of that nasty
	"undefined behavior" that makes CLC regs nervous and prone to reach
	for the nitroglycerin tablets.  In short, a perfect match.
while
    2) The kinds of problems that people are likely to encounter in their
	dead-end jobs are just the opposite.  They will almost always
	involve "undefined behavior" - either in the form of doing things
	outside the "standard" such as writing directly to hardware, using
	"graphics" or other such "hinkey" things, or by using the features
	of some greater standard (such as [stage whisper] "POSIX").  All
	things that make them off-topic for CLC.  Not to mention giving CLC
	regs heart palpations.

So, there you have it.  We should be encouraging homework problems here.

-- 
People who say they'll vote for someone else because Obama couldn't solve
all of Bush's messes are like people complaining that he couldn't cure cancer,
so they'll go and vote for cancer.

[toc] | [prev] | [next] | [standalone]

#55203

On Sunday, December 21, 2014 4:52:39 PM UTC+1, Kenny McCormack wrote:
> In article <m76n2k$8d2$1@dont-email.me>,
> James Kuyper  <jameskuyper@verizon.net> wrote:
> ...
> >The problem is not with homework, but with people who get homework
> >assignments and ask for help without having apparently even attempted to
> >solve it themselves. And that's just as much of a problem even if you're
> >teaching yourself rather than being taught by someone else.
> 
> That may be the intent, but in practice, you have to ask yourself why it is
> that if someone hits the same problem in their dead-end job and posts about
> it here (without, apparently, having done any work themselves), then
> somehow that is OK.
> 
> The over-arching point is that homework problems are exactly the kinds of
> problems that CLC is setup to handle.  We should be encouraging it, not
> discouraging it.  The reason is this:
> 
>     1) Homework problems are likely to be simple to solve, likely to be
> 	solvable using so-called "standard C", don't involve anything hinkey
> 	or real-world useable (i.e., tend to be abstractions of real-world
> 	problems) - and in general don't involve any of that nasty
> 	"undefined behavior" that makes CLC regs nervous and prone to reach
> 	for the nitroglycerin tablets.  In short, a perfect match.
> while
>     2) The kinds of problems that people are likely to encounter in their
> 	dead-end jobs are just the opposite.  They will almost always
> 	involve "undefined behavior" - either in the form of doing things
> 	outside the "standard" such as writing directly to hardware, using
> 	"graphics" or other such "hinkey" things, or by using the features
> 	of some greater standard (such as [stage whisper] "POSIX").  All
> 	things that make them off-topic for CLC.  Not to mention giving CLC
> 	regs heart palpations.
> 
> So, there you have it.  We should be encouraging homework problems here.
> 
> -- 
> People who say they'll vote for someone else because Obama couldn't solve
> all of Bush's messes are like people complaining that he couldn't cure cancer,
> so they'll go and vote for cancer.

You wrote a whole philosophy here. I am learning C programming and I find some exercises, some of exercises I make for myself inspired by exercises other peoples. If you can help, if you don't just forget it. So pal, its just a simple thing. I have problem to solve and I am looking for a solution, if someone give any info about it I appreciate if not just go to other place. I don't need advice for good manners. Just forget it, I am sick of such sheets.

[toc] | [prev] | [next] | [standalone]

#55246

Dexterr <dejangru@gmail.com> wrote:

(snip)

> You wrote a whole philosophy here. I am learning C programming and 
> I find some exercises, some of exercises I make for myself inspired 
> by exercises other peoples. If you can help, if you don't just 
> forget it. So pal, its just a simple thing. I have problem to solve 
> and I am looking for a solution, if someone give any info about 
> it I appreciate if not just go to other place. I don't need 
> advice for good manners. Just forget it, I am sick of such sheets.

As with other places in the world, better manners gets you better
treatment.  Unlike school teachers, we are not being paid to help you.
When someone helps you for free, you should be nice and help make it
easier for them.

-- glen

[toc] | [prev] | [next] | [standalone]

#55295

On 12/21/14 11:01 AM, Dexterr wrote:

> You wrote a whole philosophy here. I am learning C programming and I
> find some exercises, some of exercises I make for myself inspired by
> exercises other peoples. If you can help, if you don't just forget
> it. So pal, its just a simple thing. I have problem to solve and I am
> looking for a solution, if someone give any info about it I
> appreciate if not just go to other place. I don't need advice for
> good manners. Just forget it, I am sick of such sheets.
>


Dexterr,

It sounds like you have two goals here. The first, and most important, 
is to learn the C language. The second, and a step towards the first, is 
to come up with the answer to an exercise.

If someone just gives you the solution to the second, then the exercise 
lose most, if not all, of its value to reaching the first (and my even 
hinder your path). If your "course" (formal or via a book or tutorial) 
is at all usable to learn, the exercises should be asking you to use 
material you have already covered. (Some more challenging courses will 
have provided you the ways to discover the needed data, and are 
expecting you to do some research based on those methods to learn).

Asking for help to understand concepts you don't get can be helpful, but 
beware that sometimes the answers you get may not exactly line up with 
what the course was expecting.

Showing what you came up with, and asking if it meets the requirements 
can be helpful if the course doesn't provide good feedback, or if you 
are having trouble understanding the feedback.

If you are totally lost at this step, having someone just give you the 
answer will just put you in a deep hole. You need to restudy the section 
you are on, and maybe the previous one, to find out what you missed 
learning.

It is also possible that the "course" just isn't right for you, either 
being just a bad course, or more likely, just not the right one for YOU 
(different people learn differently and need different types of courses).

[toc] | [prev] | [next] | [standalone]

#55208

Il 21/12/2014 16:52, Kenny McCormack ha scritto:
> In article <m76n2k$8d2$1@dont-email.me>,
> James Kuyper  <jameskuyper@verizon.net> wrote:
> ...
>> The problem is not with homework, but with people who get homework
>> assignments and ask for help without having apparently even attempted to
>> solve it themselves. And that's just as much of a problem even if you're
>> teaching yourself rather than being taught by someone else.
>
> That may be the intent, but in practice, you have to ask yourself why it is
> that if someone hits the same problem in their dead-end job and posts about
> it here (without, apparently, having done any work themselves), then
> somehow that is OK.
>
> The over-arching point is that homework problems are exactly the kinds of
> problems that CLC is setup to handle.  We should be encouraging it, not
> discouraging it.  [..]

While I would normally agree on the points you made, my relatively short
experience as a human being suggests that people capable of saying
"I don't need your fucking suggestion!", are not suitable candidates as
good learners and not worth our effort to give precious advices.

-- 
Vincenzo Mercuri

[toc] | [prev] | [next] | [standalone]

Page 1 of 2  [1] 2  Next page →

Back to top | Article view | comp.lang.c

csiph-web