C++Talk.NET

jiing · Guest

I am reading a binary file *.dat, (8-bit unsigned char)
Now I want to transfer the value in it as decimal, how can I do ?
Thanks in advance.

ifstream fin("usb1_8192_out.dat", ios::binary | ios::in );
if (!fin.is_open() ){
cout<<"File is not open."< }else{
cout<<"File is open."< }

char ch ;
int buffer[8192];

while( !fin.eof() ){
fin.get(ch);
cout< this?
}
fin.close();

Karl Heinz Buchegger · Guest

jiing wrote:

jiing · Guest

Karl, thank you for your kind help.

But I still have some problem

int i = 0;
char ch ;
vector<int> buffer;
long sum = 0;

while( fin.get( ch ) ) {
buffer.push_back( (unsigned int)ch );
i++;
}
fin.close();
// calculate mean
for(i=1; i<=10; i++){
cout< }

for(int i=0; i sum = sum + buffer[i];
}

The output is: -121 117 103 -80 -93 57 120
-36 108 47
But when I see the binary file, they are
7F 87 75 67 B0 A3 39 78 DC 6C
ïŠ›gé™¤9xé‡¿

They real value I wanted should be
127 135 117 103 176 163 57 120 220 108

Can anyone teach me. I can not figure out what mistack I made.
Thank you.

cafeeee · Guest

int i = 0;
char ch ;
vector<int> buffer;
long sum = 0;

while( fin.get( ch ) ) {
buffer.push_back( (int)ch ); // change "unsigned int" to "int"
i++;
}
fin.close();
// calculate mean
for(i=0; i element of "buffer"
cout< }

for(int i=0; i sum = sum + buffer[i];
}

jiing · Guest

cafeeee, thank you,

But I have one question
After revising, the first 10 result still have some negative
so I add the with 256 if them are negative, and get what I want
But I am not very sure why I can not cast them as unsigned int
can anyone teach me? thank you.

ifstream fin("usb1_8192k_out.dat", ios::binary | ios::in );
if (!fin.is_open() ){
cout<<"input file is not open."< }
char ch ;
vector while( fin.get( ch ) ){
int temp;
(int(ch) < 0)?(temp = int(ch)+256):(temp = int(ch) ); // I added
this line
buffer.push_back(temp);
}
fin.close();

// calculate mean
for(int i=0; i<10; i++){
cout< }

Karl Heinz Buchegger · Guest

jiing wrote:

Rolf Magnus · Guest

jiing wrote:

jiing · Guest

Thanks for your answering.

but the file get function seems can not deal with unsigned char

when I revise the code as follows:

unsigned char ch ;
vector<int> buffer;
while( fin.get( ch ) ){

The compiler tells me
36 C:usb_check_lost_2.cpp no matching function for call to
`std::basic_ifstream<char, std::char_traits::get(unsigned
char&)'

Kurious · Guest

Hi guys,

I'm crossing my fingers and hoping someone out there is familiar with
embedding perl into C++...

I'm trying to do that using the following code:

char *embedding[] = { "", "drawGraph.pl", "0" };
my_perl = perl_alloc();
perl_construct( my_perl );
perl_parse(my_perl, NULL, 3, embedding, NULL);
perl_run(my_perl);
perl_call_argv("drawGraph", G_DISCARD | G_NOARGS, embedding);

Now this calls the subroutine drawGraph in the file drawGraph.pl ok if
there are no modules being included. However as soon as I include the
line
use GD::Graph::bars;
it crashes. I'm assuming it has something to do with what is described
on this page:
http://www.monster-submit.com/resources/docs/modules/pod/perlembed.html#Using_Perl_modules_which_themse
however I have been unable to implement that solution. After adding
the code thus:

#ifdef __cplusplus
# define EXTERN_C extern "C"
#else
# define EXTERN_C extern
#endif

static void xs_init _((void));

EXTERN_C void boot_DynaLoader _((CV* cv));
EXTERN_C void boot_Socket _((CV* cv));

EXTERN_C void
xs_init()
{
char *file = __FILE__;
/* DynaLoader is a special case */
newXS("DynaLoader::boot_DynaLoader", boot_DynaLoader, file);
newXS("Socket::bootstrap", boot_Socket, file);
}

When compiling I get the error:

linkage specification contradicts earlier specification for 'xs_init'
D:......PerlThingPerlThingDlg.cpp(187) : see declaration of
'xs_init'

followed by two:
error C2664: 'Perl_newXS' : cannot convert parameter 3 from 'void
(struct cv *)' to 'void (__cdecl *)(struct interpreter *,struct cv *)'
None of the functions with this name in scope match the target
type

I have been unable to find where to go from here. I don't really
understand what's going on, and I haven't been able to find a resource
that explains this. What's going on here, and what am I missing? Is
there an easier way around this? Is there something I should have read
up on before posting?

Thanks guys,

Hyde

Julián Albo · Guest

Kurious wrote:

Kurious · Guest

On Tue, 17 May 2005 15:46:56 +0200, Julián Albo <JULIANALBO (AT) terra (DOT) es>
wrote: