Questions tagged [unsigned-char]
321 questions
6
votes
1 answer
Converting from C++ string to unsigned char* and back
What would be the code to convert an std::string to unsigned char* and back?
str = "1234567891234567"
unsigned char* unsignedStr = ConvertStrToUnsignedCharPointer(str);
str1 = ConvertUnsignedCharToStr(unsignedStr);
str and str1 must be same with no…
Sahil
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6
votes
1 answer
Casting from `int` to `unsigned char`
I am running the following C++ code on Coliru:
#include
#include
int main()
{
int num1 = 208;
unsigned char uc_num1 = (unsigned char) num1;
std::cout << "test1: " << uc_num1 << "\n";
int num2 = 255;
…
user4063326
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6
votes
1 answer
How do I #define an unsigned char* string?
I have following define in my code
#define PRODUCTNAME "SomeName"
and I want to send it with a function com_reply(unsigned char* msg, uint16_t lenght).
Now I get a warning that my argument differs in signedness. I know what the problem is and…
Dehalion
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6
votes
1 answer
How to read in binary data and cast to unsigned char (C++)
I have a raw image file that is saved in binary data (no encoding). I want to read in the file and cast the values to an unsigned char. But I'm not sure how to begin going about doing this. Each file contains 640x480 bytes. Each pixel is 8bits.
I've…
c0d3rz
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5
votes
4 answers
Difference between unsigned char and char pointers
I'm a bit confused with differences between unsigned char (which is also BYTE in WinAPI) and char pointers.
Currently I'm working with some ATL-based legacy code and I see a lot of expressions like the following:
CAtlArray…
Yippie-Ki-Yay
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5
votes
1 answer
Unexpected behaviour on underflow of unsigned char
The following program:
#include
#include
int main ()
{
unsigned char result1 {0};
unsigned char result2 {0};
result1 = (result1 - 1) % 8;
result2 = result2 - 1;
result2 = result2 % 8;
std::cout <<…
JosF
- 53
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5
votes
3 answers
Initializing an unsigned char array with hex values in C++
I would like to initialize an unsigned char array with 16 hex values. However, I don't seem to know how to properly initialize/access those values. When I try to access them as I might want to intuitively, I'm getting no value at all.
This is my…
hatgirl
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5
votes
3 answers
Casting from unsigned into signed char in C
I am converting an input raw pcm stream into mp3 using lame. The encoding function within that library returns mp3 encoded samples in an array of type unsigned char. This mp3-encoded stream now needs to be placed within an flv container which uses a…
Sriram
- 10,298
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5
votes
5 answers
Generating random unsigned char values in C++
I was wondering how to generate random unsigned char values. My idea;
rand()%255; since unsigned chars support between 0-255. I was wondering if this method could be improved(or is it the most legit way to do this)
Ali
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4
votes
1 answer
Wrap python list to unsigned char*
Edit : Hi all !!
I'm currently trying to access to C++ functions from Python and I'm facing to a problem when I try to pass Python list as argument to a function.
here is the C++ function definition I'm trying to access (used to send command to…
Gojir4
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4
votes
3 answers
How to initialize unsigned char pointer
I want to initialize an unsigned char * buffer of length 1500 so that I can store values in it from some other sources.
Amit
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4
votes
3 answers
Signed and unsigned char
Why are two char like signed char and unsigned char with the same value not equal?
char a = 0xfb;
unsigned char b = 0xfb;
bool f;
f = (a == b);
cout << f;
In the above code, the value of f is 0.
Why it's so when both a and b have the same value?
T.g
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4
votes
4 answers
for (unsigned char i = 0; i<=0xff; i++) produces infinite loop
Why does the following c code end up in an infinite loop?
for(unsigned char i = 0; i <= 0xff; i++){}
It is the same result with:
for(unsigned char i = 0; i <= 0xff; ++i){}
In which way do I have to modify the code, to get it working as expected…
fragwürdig
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4
votes
2 answers
Convert unsigned char array into uint8_t array?
I need convert unsigned char array into unit8_t array maybe someone has an idea how to do it?
I tried to look for information on the Internet, but unfortunately I did not succeed.
:)
Mantas Pranckūnas
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4
votes
5 answers
Is the signedness of char an interface issue?
Suppose I have a function
void foo(char *)
which, internally, needs to treat its input as a block of NUL-terminated bytes (say, it's a hash function on strings). I could cast the argument to unsigned char* in the function. I could also change the…
Fred Foo
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