Copying Few Octets from Vector

[smilesonisamal]

Hi all,
I am facing difficulty in copying few octets from a vector to a
buffer.

typedef unsigned char uint8_t;
I have a vector std::vector<uint8_t*> m_Data;
which contains the following octets. I want to copy (30 74 64 230 0 8)
to a buffer. I saw in the web and got code where iterator is used to
copy all the octets not partial elements. How will I retrieve 6 octets
from the vector? I am new to C++ and facing lot of problems in
conversion. I tried a lot but couldnot succeed.Could anybody help me
in this regard?
Any example source code will be great help.

Vector Elements
-------------------------
1 0 94 0 0 2 0 30 74 64 230 0 8 0 69 0 0 48 0 0 0 0 1 17 168 216 146
223 158 3 2
24 0 0 2 7 193 7 193 0 28 81 57 0 0 8 3 10 100 5 0 99 105 115 99 111 0
0 0 146 2
23 158 1

Regards
Soni

 

[Victor Bazarov]

Hi all,
I am facing difficulty in copying few octets from a vector to a
buffer.

What kind of difficulty?

typedef unsigned char uint8_t;
I have a vector std::vector<uint8_t*> m_Data;
which contains the following octets. I want to copy (30 74 64 230 0 8)
to a buffer. I saw in the web and got code where iterator is used to
copy all the octets not partial elements. How will I retrieve 6 octets
from the vector? I am new to C++ and facing lot of problems in
conversion.

"In conversion"? To and from what?

> I tried a lot but couldnot succeed.Could anybody help me
in this regard?

Yes, we can help. What have you tried? Post your code.

Any example source code will be great help.

Show us yours and we'll show you ours. Oh, and while you're at it,
check out FAQ 5.2, please. You can find the FAQ list here:
http://www.parashift.com/c++-faq-lite/

Vector Elements
-------------------------
1 0 94 0 0 2 0 30 74 64 230 0 8 0 69 0 0 48 0 0 0 0 1 17 168 216 146
223 158 3 2
24 0 0 2 7 193 7 193 0 28 81 57 0 0 8 3 10 100 5 0 99 105 115 99 111 0
0 0 146 2
23 158 1

V

 

[smilesonisamal]

What kind of difficulty?


"In conversion"?  To and from what?

 > I tried a lot but couldnot succeed.Could anybody help me


Yes, we can help.  What have you tried?  Post your code.


Show us yours and we'll show you ours.  Oh, and while you're at it,
check out FAQ 5.2, please.  You can find the FAQ list here:http://www.parashift.com/c++-faq-lite/




V

Hi,

I have tried and could not succeed.

std::vector<uint8_t*> m_Data;

unsigned char*
GetData(unsigned long octetOffset)
{

unsigned long bufferLength = m_Data.size() - octetOffset;
uchar* buffer = new uchar[bufferLength];

// Copy the packet data buffer
const_iterator it = m_Data.begin() + octetOffset;

int octet = 0;
for (; it != m_Data.end(); ++it, ++octet)
buffer[octet] = *it;


return buffer;

}

Regards
Soni

 

[Victor Bazarov]

Hi,

I have tried and could not succeed.

What exactly isn't working? Did you read the FAQ? If you haven't,
please do, and pay close attention to FAQ 5.8.

std::vector<uint8_t*> m_Data;

unsigned char*
GetData(unsigned long octetOffset)
{

unsigned long bufferLength = m_Data.size() - octetOffset;
uchar* buffer = new uchar[bufferLength];

// Copy the packet data buffer
const_iterator it = m_Data.begin() + octetOffset;

int octet = 0;
for (; it != m_Data.end(); ++it, ++octet)
buffer[octet] = *it;


return buffer;

}

V

 

[smilesonisamal]

  I have tried and could not succeed.

What exactly isn't working?  Did you read the FAQ?  If you haven't,
please do, and pay close attention to FAQ 5.8.

std::vector<uint8_t*>   m_Data;

unsigned char*
GetData(unsigned long octetOffset)
{

unsigned long bufferLength = m_Data.size() - octetOffset;
uchar* buffer = new uchar[bufferLength];

   // Copy the packet data  buffer
  const_iterator it = m_Data.begin() + octetOffset;

   int octet = 0;
   for (; it != m_Data.end(); ++it, ++octet)
      buffer[octet] = *it;

   return buffer;

}

V

Actually I have written the code for copying the whole packets to the
packet buffer. What I dont know is how to extract 6 octet from the
position-0 in vector.

 

[Victor Bazarov]

[..]
Actually I have written the code for copying the whole packets to the
packet buffer. What I dont know is how to extract 6 octet from the
position-0 in vector.

Let me see if I understand you. You have a vector of elements, like
several hundreds long, right? And you don't know how to get the first
six elements from that vector? That can't be right. Again, I don't
exactly understand what you're saying, most likely.

V

 

[Alf P. Steinbach]

* (e-mail address removed):

Hi all,
I am facing difficulty in copying few octets from a vector to a
buffer.

typedef unsigned char uint8_t;
I have a vector std::vector<uint8_t*> m_Data;
which contains the following octets. I want to copy (30 74 64 230 0 8)
to a buffer. I saw in the web and got code where iterator is used to
copy all the octets not partial elements. How will I retrieve 6 octets
from the vector? I am new to C++ and facing lot of problems in
conversion. I tried a lot but couldnot succeed.Could anybody help me
in this regard?
Any example source code will be great help.

Vector Elements
-------------------------
1 0 94 0 0 2 0 30 74 64 230 0 8 0 69 0 0 48 0 0 0 0 1 17 168 216 146
223 158 3 2
24 0 0 2 7 193 7 193 0 28 81 57 0 0 8 3 10 100 5 0 99 105 115 99 111 0
0 0 146 2
23 158 1

Regards
Soni

Please explain your data structure.

You have a vector of pointers.

Is it the first pointer in the vector that points to the data listed above?

How do you know the data size?

Also, please explain exactly what you're trying to accomplish.


Cheers & hth.,

- Alf

 

[smilesonisamal]

* (e-mail address removed):







Please explain your data structure.

You have a vector of pointers.

Is it the first pointer in the vector that points to the data listed above?

First pointer of vector points to first element of the vector.

How do you know the data size? m_Data.size()

Also, please explain exactly what you're trying to accomplish.

Basically Iam trying to get the first 6 octets of the ethernet packet
(destination mac address) from the packet(decimal format) and try to
compare with the a different mac address. if they are same I need to
do some more operation. All the octets are stored in a vector.

Cheers & hth.,

- Alf

For Victor
-----------
Actually I found lot of examples in vector which traverses from begin
to end. What I understand is a iterator traverses an object. Am I
right? If I will have the code as below:

for (it=m_Data.begin(); it<6; it++)
Its gonna fail in compilation.Am I right?

 

[Alf P. Steinbach]

* (e-mail address removed):

First pointer of vector points to first element of the vector.

The first vector element points to itself?

The first vector element points to the first element of some raw array?

What?

m_Data.size()

You have a vector of pointers.

The number of pointers is quite likely not the size of your numerical data shown
above.

Basically Iam trying to get the first 6 octets of the ethernet packet
(destination mac address) from the packet(decimal format) and try to
compare with the a different mac address.

What do you mean by "decimal format".


Cheers & hth.,

- Alf

 

[James Kanze]

I am facing difficulty in copying few octets from a vector to a
buffer.

typedef unsigned char uint8_t;
I have a vector std::vector<uint8_t*> m_Data;

I'm not sure about the rest, but this vector doesn't contain
octets; it contains pointers.

which contains the following octets.

And none follow. So we have a vector which contains
pointers, and there are no octets. So far, so good.

I want to copy (30 74 64 230 0 8) to a buffer.

Where do these octets come from?

I saw in the web and got code where iterator is used to
copy all the octets not partial elements. How will I
retrieve 6 octets from the vector?

If the vector contains pointers, you can't. All you can get
from it is pointers.

Supposing you have a vector of octets:
std::vector< uint8_t > data ;
*and* supposing that offset plus length are less than the
size, you can copy the first length octets, starting from
offset, using std::copy:
std::copy( data.begin() + offset,
data.begin() + offest + length,
destination ) ;
You'd best check that offset + length <= data.size()
beforehand, though.

 

[James Kanze]

BTW: you shouldn't write this typedef yourself. You should

You just explained it for him.

First pointer of vector points to first element of the
vector.

That's not possible, since the first pointer in the vector
has type uint8_t*, which is, of course, the same type as the
elements in the vector. And to point to an element of this
type, you'd need a uint8_t**.

m_Data.size()

That's the number of pointers in the vector.

Basically Iam trying to get the first 6 octets of the
ethernet packet (destination mac address) from the
packet(decimal format) and try to compare with the a
different mac address. if they are same I need to do some
more operation. All the octets are stored in a vector.

You're still not very clear. First, do you have octets, or
decimal format? And what is the data structure which holds
them? If all of the octets are stored in a vector, then you
have octets, and not decimal format (which is text). And
that vector has the type std::vector< uint8_t >. And
getting the first six is trivial, using begin() and begin()
+ 6. (Provided, of course, that there are 6 or more octets
in the vector.)

 

[smilesonisamal]

BTW: you shouldn't write this typedef yourself.  You should


You just explained it for him.


That's not possible, since the first pointer in the vector
has type uint8_t*, which is, of course, the same type as the
elements in the vector.  And to point to an element of this
type, you'd need a uint8_t**.


That's the number of pointers in the vector.


You're still not very clear.  First, do you have octets, or
decimal format?  And what is the data structure which holds
them?  If all of the octets are stored in a vector, then you
have octets, and not decimal format (which is text).  And
that vector has the type std::vector< uint8_t >.  And
getting the first six is trivial, using begin() and begin()
+ 6.  (Provided, of course, that there are 6 or more octets
in the vector.)

I have a sequence of octets as mentioned in my earlier qs. I have
stored it in a vector which contains series of octets.(uint_8*). I
want to get the traverse through the series of octets from offset=0
till the 6th element and compare with a mac address that i have
already in a string format(00:00:00:00:00:01-> converted to
string-48,48,ascii)). I want to use strcmp/memcmp or something to
compare once i extract 6 octets from the offset=0 from the sequence of
octets from vector. If they are equal i want to do some operations.
The octets are read from a binary file.
Could you please help me in this regard? Some example code will be
helpful for me.

 

[SG]

I have a sequence of octets as mentioned in my earlier qs. I have
stored it in a vector which contains series of octets.(uint_8*).

How?

How's a sequence of pointers (uint_8*) a sequence of octets?

I
want to get the traverse through the series of octets from offset=0
till the 6th element and compare with a mac address that i have
already in a string format(00:00:00:00:00:01-> converted to
string-48,48,ascii)). I want to use strcmp/memcmp or something to
compare once i extract 6 octets from the offset=0 from the sequence of
octets from vector.
Understood.

[...] Could you please help me in this regard? Some example code
will be helpful for me.

Indeed it would. Show some code --- because we don't have a clue about
how you stored your MAC address in the vector of *pointers*.

Cheers!
SG

 

[James Kanze]

On Apr 11, 12:34 am, James Kanze <[email protected]> wrote:

[...]

I have a sequence of octets as mentioned in my earlier qs. I
have stored it in a vector which contains series of
octets.(uint_8*).

If the vector is std::vector< uint_8* >, it contains a sequence
of pointers, not a sequence of octets. You're still
contradicting yourself, which is why we're having trouble
understanding the problem.

I want to get the traverse through the series of octets from
offset=0 till the 6th element and compare with a mac address
that i have already in a string format(00:00:00:00:00:01->
converted to string-48,48,ascii)). I want to use
strcmp/memcmp or something to compare once i extract 6 octets
from the offset=0 from the sequence of octets from vector. If
they are equal i want to do some operations. The octets are
read from a binary file. Could you please help me in this
regard? Some example code will be helpful for me.

Until we know how and where these octets are stored, it's
difficult to say much. If they are stored in a vector
(std::vector< uint8_t >), then it's easy using std::copy or
std::equal---I seem to remember having already posted the code.
If they're stored somewhere else, then no one can answer until
we know where they are stored.

 

[smilesonisamal]

On Apr 11, 12:34 am, James Kanze <[email protected]> wrote:

    [...]

I have a sequence of octets as mentioned in my earlier qs. I
have stored it in a vector which contains series of
octets.(uint_8*).

If the vector is std::vector< uint_8* >, it contains a sequence
of pointers, not a sequence of octets.  You're still
contradicting yourself, which is why we're having trouble
understanding the problem.

I want to get the traverse through the series of octets from
offset=0 till the 6th element and compare with a mac address
that i have already in a string format(00:00:00:00:00:01->
converted to string-48,48,ascii)). I want to use
strcmp/memcmp or something to compare once i extract 6 octets
from the offset=0 from the sequence of octets from vector. If
they are equal i want to do some operations.  The octets are
read from a binary file.  Could you please help me in this
regard? Some example code will be helpful for me.

Until we know how and where these octets are stored, it's
difficult to say much.  If they are stored in a vector
(std::vector< uint8_t >), then it's easy using std::copy or
std::equal---I seem to remember having already posted the code.
If they're stored somewhere else, then no one can answer until
we know where they are stored.

--
James Kanze (GABI Software)             email:[email protected]
Conseils en informatique orientée objet/
                   Beratung in objektorientierter Datenverarbeitung
9 place Sémard, 78210 St.-Cyr-l'École, France, +33 (0)1 30 23 00 34

I fixed the problem extracting the 6 octets into a vector. Thanks for
all your help. I have only one problem now. If I have a sequence of
octets (1 0 94 0 0 2). I used std::copy and it worked. How will I make
these to ASCII string?Could you please help me in this regard?

 

[smilesonisamal]

On Apr 12, 7:18 am, (e-mail address removed) wrote:

    [...]

I have a sequence of octets as mentioned in my earlier qs. I
have stored it in a vector which contains series of
octets.(uint_8*).

If the vector is std::vector< uint_8* >, it contains a sequence
of pointers, not a sequence of octets.  You're still
contradicting yourself, which is why we're having trouble
understanding the problem.

Until we know how and where these octets are stored, it's
difficult to say much.  If they are stored in a vector
(std::vector< uint8_t >), then it's easy using std::copy or
std::equal---I seem to remember having already posted the code.
If they're stored somewhere else, then no one can answer until
we know where they are stored.

--
James Kanze (GABI Software)             email:[email protected]
Conseils en informatique orientée objet/
                   Beratung in objektorientierter Datenverarbeitung
9 place Sémard, 78210 St.-Cyr-l'École, France, +33 (0)1 30 23 00 34

I fixed the problem extracting the 6 octets into a vector. Thanks for
all your help. I have only one problem now. If I have a sequence of
octets (1 0 94 0 0 2). I used std::copy and it worked. How will I make
these to ASCII string?Could you please help me in this regard?

I have written the small program in VC++ and it gives lot of errors.
Could you please help me in this regard?
My objective is to convert the {1 0 94 0 0 2} which is stored in a
vector to convert to ASCII string formatted MAC address.

#include "stdafx.h"
#include<iostream>
#include<string>
#include<vector>
using namespace std;

int main ()
{
vector<unsigned char> (pOctets);
pOctets.resize(0);
pOctets.reserve(6);
pOctets.push_back("1");
pOctets.push_back("0");
pOctets.push_back("94");
pOctets.push_back("0");
pOctets.push_back("0");
pOctets.push_back("2");

unsigned char* buffer = new unsigned[6];
const iterator it= pOctets.begin();
int octet = 0;
for (; it != pOctets.end(); ++it, ++octet)
buffer[octet] = *it;

char* buf = ConvertMacStringFromDecimal(buffer);


}
char*
ConvertMacStringFromDecimal(unsigned char* buf) const
{
char temp[100];
sprintf(temp,("%x:%x:%x:%x:%x:%x"),
unsigned long ((buf >> 40) & 0xff),
unsigned long ((buf >> 32) & 0xff),
unsigned long ((buf >> 24) & 0xff),
unsigned long ((buf >> 16) & 0xff),
unsigned long ((buf >> 8) & 0xff)
);
return temp ;
}


Can somebody help me in this regard?

------ Build started: Project: test1, Configuration: Debug Win32 ------

1>Compiling...
1>test1.cpp
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(15) : error C2664:
'std::vector<_Ty>:ush_back' : cannot convert parameter 1 from 'const
char [2]' to 'const unsigned char &'
1> with
1> [
1> _Ty=unsigned char
1> ]
1> Reason: cannot convert from 'const char [2]' to 'const
unsigned char'
1> There is no context in which this conversion is possible
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(16) : error C2664:
'std::vector<_Ty>:ush_back' : cannot convert parameter 1 from 'const
char [3]' to 'const unsigned char &'
1> with
1> [
1> _Ty=unsigned char
1> ]
1> Reason: cannot convert from 'const char [3]' to 'const
unsigned char'
1> There is no context in which this conversion is possible
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(17) : error C2664:
'std::vector<_Ty>:ush_back' : cannot convert parameter 1 from 'const
char [4]' to 'const unsigned char &'
1> with
1> [
1> _Ty=unsigned char
1> ]
1> Reason: cannot convert from 'const char [4]' to 'const
unsigned char'
1> There is no context in which this conversion is possible
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(18) : error C2664:
'std::vector<_Ty>:ush_back' : cannot convert parameter 1 from 'const
char [3]' to 'const unsigned char &'
1> with
1> [
1> _Ty=unsigned char
1> ]
1> Reason: cannot convert from 'const char [3]' to 'const
unsigned char'
1> There is no context in which this conversion is possible
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(19) : error C2664:
'std::vector<_Ty>:ush_back' : cannot convert parameter 1 from 'const
char [3]' to 'const unsigned char &'
1> with
1> [
1> _Ty=unsigned char
1> ]
1> Reason: cannot convert from 'const char [3]' to 'const
unsigned char'
1> There is no context in which this conversion is possible
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(20) : error C2664:
'std::vector<_Ty>:ush_back' : cannot convert parameter 1 from 'const
char [3]' to 'const unsigned char &'
1> with
1> [
1> _Ty=unsigned char
1> ]
1> Reason: cannot convert from 'const char [3]' to 'const
unsigned char'
1> There is no context in which this conversion is possible
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(22) : error C2440:
'initializing' : cannot convert from 'unsigned int *' to 'unsigned
char *'
1> Types pointed to are unrelated; conversion requires
reinterpret_cast, C-style cast or function-style cast
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(23) : error C2514:
'std::iterator' : class has no constructors
1> c:\program files\microsoft visual studio 8\vc\include
\xutility(486) : see declaration of 'std::iterator'
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::vector<_Ty,_Alloc> &,const
std::vector<_Ty,_Alloc> &)' : could not deduce template argument for
'const std::vector<_Ty,_Alloc> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\vector
(1268) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::vector<_Ty,_Alloc> &,const
std::vector<_Ty,_Alloc> &)' : could not deduce template argument for
'const std::vector<_Ty,_Alloc> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\vector
(1268) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::istream_iterator<_Ty,_Elem,_Traits,_Diff>
&,const std::istream_iterator<_Ty,_Elem,_Traits,_Diff> &)' : could not
deduce template argument for 'const
std::istream_iterator<_Ty,_Elem,_Traits,_Diff> &' from 'const
std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include
\iterator(277) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::istream_iterator<_Ty,_Elem,_Traits,_Diff>
&,const std::istream_iterator<_Ty,_Elem,_Traits,_Diff> &)' : could not
deduce template argument for 'const
std::istream_iterator<_Ty,_Elem,_Traits,_Diff> &' from 'const
std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include
\iterator(277) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::basic_string<_Elem,_Traits,_Alloc> &,const
_Elem *)' : could not deduce template argument for 'const
std::basic_string<_Elem,_Traits,_Alloc> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\string
(121) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::basic_string<_Elem,_Traits,_Alloc> &,const
_Elem *)' : could not deduce template argument for 'const
std::basic_string<_Elem,_Traits,_Alloc> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\string
(121) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const _Elem *,const
std::basic_string<_Elem,_Traits,_Alloc> &)' : could not deduce
template argument for 'const _Elem *' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\string
(111) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::basic_string<_Elem,_Traits,_Alloc> &,const
std::basic_string<_Elem,_Traits,_Alloc> &)' : could not deduce
template argument for 'const std::basic_string<_Elem,_Traits,_Alloc>
&' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\string
(101) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::basic_string<_Elem,_Traits,_Alloc> &,const
std::basic_string<_Elem,_Traits,_Alloc> &)' : could not deduce
template argument for 'const std::basic_string<_Elem,_Traits,_Alloc>
&' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\string
(101) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::allocator<_Ty> &,const
std::allocator<_Other> &) throw()' : could not deduce template
argument for 'const std::allocator<_Ty> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\xmemory
(181) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::allocator<_Ty> &,const
std::allocator<_Other> &) throw()' : could not deduce template
argument for 'const std::allocator<_Ty> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\xmemory
(181) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::istreambuf_iterator<_Elem,_Traits> &,const
std::istreambuf_iterator<_Elem,_Traits> &)' : could not deduce
template argument for 'const std::istreambuf_iterator<_Elem,_Traits>
&' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include
\xutility(2152) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::istreambuf_iterator<_Elem,_Traits> &,const
std::istreambuf_iterator<_Elem,_Traits> &)' : could not deduce
template argument for 'const std::istreambuf_iterator<_Elem,_Traits>
&' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include
\xutility(2152) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::reverse_iterator<_RanIt> &,const
std::reverse_iterator<_RanIt2> &)' : could not deduce template
argument for 'const std::reverse_iterator<_RanIt> &' from 'const
std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include
\xutility(1834) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std::reverse_iterator<_RanIt> &,const
std::reverse_iterator<_RanIt2> &)' : could not deduce template
argument for 'const std::reverse_iterator<_RanIt> &' from 'const
std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include
\xutility(1834) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std:air<_Ty1,_Ty2> &,const
std:air<_Ty1,_Ty2> &)' : could not deduce template argument for
'const std:air<_Ty1,_Ty2> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\utility
(68) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2784: 'bool
std:perator !=(const std:air<_Ty1,_Ty2> &,const
std:air<_Ty1,_Ty2> &)' : could not deduce template argument for
'const std:air<_Ty1,_Ty2> &' from 'const std::iterator'
1> c:\program files\microsoft visual studio 8\vc\include\utility
(68) : see declaration of 'std:perator !='
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2676: binary '!=' :
'const std::iterator' does not define this operator or a conversion to
a type acceptable to the predefined operator
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(25) : error C2675: unary '++' :
'const std::iterator' does not define this operator or a conversion to
a type acceptable to the predefined operator
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(26) : error C2100: illegal
indirection
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(26) : error C2440: '=' : cannot
convert from 'const std::iterator' to 'unsigned char'
1> No user-defined-conversion operator available that can
perform this conversion, or the operator cannot be called
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(28) : error C3861:
'ConvertMacStringLong': identifier not found
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(34) : error C2270:
'ConvertMacStringLong' : modifiers not allowed on nonmember functions
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(34) : error C2365:
'ConvertMacStringLong' : redefinition; previous definition was
'formerly unknown identifier'
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(37) : warning C4293: '>>' : shift
count negative or too big, undefined behavior
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(37) : error C2296: '>>' : illegal,
left operand has type 'unsigned char *'
1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(37) : fatal error C1903: unable to
recover from previous error(s); stopping compilation
1>Build log was saved at "file://c:\Documents and Settings\soni\My
Documents\Visual Studio 2005\Projects\test1\test1\Debug\BuildLog.htm"
1>test1 - 34 error(s), 1 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped
==========

 

[SG]

I have written the small program in VC++ and it gives lot of errors.
[...]

[horrible piece of pseudo C++ code removed]

[...]
Can somebody help me in this regard?

Sure. The kinds of posts you wrote imply that you
- lack basic programming experiences (language agnostic)
- don't understanding the basics of C++

What to do about it?
- get a book/tutor for learning the C++ language
- get a book/tutor for learning programming

As a bonus -- I feel generous today -- let me decipher a couple of
compiler error messages for you:

1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(15) : error C2664:
'std::vector<_Ty>:ush_back' : cannot convert parameter 1 from 'const
char [2]' to 'const unsigned char &'
1>        with
1>        [
1>            _Ty=unsigned char
1>        ]
1>        Reason: cannot convert from 'const char [2]' to 'const
unsigned char'
1>        There is no context in which this conversion is possible

The literal "1" in push_back("1") is of type const char[2]. It's a
char array containing the character for the decimal one and a
terminating zero. Your vector stores unsigned char. There is no
conversion from char[2] to unsigned char.

In the case of push_back("94") the type of the argument is const char
[3].

etc

1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(22) : error C2440:
'initializing' : cannot convert from 'unsigned int *' to 'unsigned
char *'
1>        Types pointed to are unrelated; conversion requires
reinterpret_cast, C-style cast or function-style cast

You wrote

unsigned char* something = new unsigned[6];

"new unsigned[6]" is an expression that returns a pointer to an
unsigned integer. You seem to have forgotten the "char" after
"unsigned" in the new expression.

1>c:\documents and settings\soni\my documents\visual studio
2005\projects\test1\test1\test1.cpp(23) : error C2514:
'std::iterator' : class has no constructors
1>        c:\program files\microsoft visual studio 8\vc\include
\xutility(486) : see declaration of 'std::iterator'

due to the line

const iterator it= pOctets.begin();

You used a using directive and pulled a lot of names into your global
scope. One of those names seems to be "iterator" (std::iterator from
the <iterator> header). This is NOT the iterator you want. In fact,
std::iterator *is* no iterator. It's just a base class that contains
some typedefs. You want to use your vector's iterator instead.


Cheers!
SG

 

[James Kanze]

I fixed the problem extracting the 6 octets into a vector.
Thanks for all your help. I have only one problem now. If I
have a sequence of octets (1 0 94 0 0 2). I used std::copy and
it worked. How will I make these to ASCII string?Could you
please help me in this regard?

It depends. A priori, you'll use an ostream, but that's just a
start. What is the format of the ASCII string? Where does the
ASCII string go (in an std::string, to a file...)?

 

[smilesonisamal]

It depends.  A priori, you'll use an ostream, but that's just a
start.  What is the format of the ASCII string?  Where does the
ASCII string go (in an std::string, to a file...)?

--
James Kanze (GABI Software)             email:[email protected]
Conseils en informatique orientée objet/
                   Beratung in objektorientierter Datenverarbeitung
9 place Sémard, 78210 St.-Cyr-l'École, France, +33 (0)1 30 23 00 34

Hi all,
Finally I succeed with my experiment . What I did is I extracted
the 6 octets into a vector and then used ostream/istream. Thanks for
your all your support. Special thanks to SG and James...