Questions tagged [unsigned-char]
321 questions
-1
votes
1 answer
convert struct to unsigned char through overloaded operator << and >> (see update)
I have this struct with 2 attributes (one char and one int, for a memory usage of 3 bytes:
struct Node {
char data;
int frequency;
}
I try overload the operators << and >> for this struct, for being able to read and write this struct from…
Kleber Mota
- 8,521
- 31
- 94
- 188
-1
votes
3 answers
Char addition does not have expected result in C
Can someone explain me how is this at the end
a=?,b=?,c=-124
and not
a=?,b=?,c=132
This is code:
#include
int main() {
char a = 'D', b='C', c='A';
a = c + 'D';
b = a + b + 'A';
c = b - a;
a = a - b + 'C';
b = b - 68;
…
mr fahrenheit
- 23
- 5
-1
votes
1 answer
Appending an unsigned char to a vector changes its value
I have the following 2D vector:
vector> dates;
I also have the following unsigned char array:
unsigned char date[3] = {1, 18, 108};
When I push_back this array to dates it sets all the unsigned char elements to 204:
date =…
brickbobed
- 169
- 1
- 10
-1
votes
1 answer
Return unsigned char array to main function
Background: My original main() is:
int main(int argc, char *argv[])
{
unsigned char output[16] = {0x00}; // copied from code
// .... (some steps to calculate output[i])
for (i = 0; i < 16; i++)
{
printf("%02X ",…
TJCLK
- 183
- 12
-1
votes
2 answers
Using a vector of unsigned chars in a map
I need help using unsigned chars in std::vectors that are inside of a std::map.
This is how I declare the std::map:
std::map> DataMap;
The problem comes when I try to assign a std::vector to the std::map.
it->first…
JackCross
- 37
- 5
-1
votes
1 answer
C function to read binary file doesn't work if used by other function.?
I wrote this function to return an unsigned char * containing the data from any file(using rbread mode) it looks like this:
uchar * get_file_data (char *f_name, luint *len) {
// verify file
struct stat sBuffer;
int iRc;
iRc =…
Otard95
- 3
- 4
-1
votes
3 answers
Converting an int to an unsigned char in C
I've never needed to use unsigned char before, but I've recently became curious about their ability to store integers. Through a little bit of reading I have done I've found that the cast from int to unsigned char is done implicitly, but I have also…
Derek
- 11
- 4
-1
votes
2 answers
Is this Integer Promotion? How does it work?
I was just experimenting and I tried out two printf()s.
unsigned char a = 1;
a = ~a;
printf("----> %x %x %x %x", ~a, a, ~a, ++a);
This one gave the output
----> ffffff00 ff ffffff00 ff
Next one was
unsigned char a = 1;
printf("----> %x %x %x %x",…
Tattu
- 327
- 1
- 3
- 15
-1
votes
2 answers
Converting an integer to an hexadecimal unsigned char array in C++
I need to convert an integer int parameter to an hexadecimal unsigned char buffer[n].
If integer is for example 10 then the hexadecimal unsigned char array should be 0x0A
To do so I have the following code:
int parameter;
std::stringstream…
Cristina
- 21
- 1
- 5
-1
votes
1 answer
Remove first bytes of a unsigned char*
I'm currently working on a project where I need to work with unsigned char* and unwanted bytes in there. I'll describe the situation:
1/ I have an iOS app that loads an image (UIImage).
2/ I transform this UIImage into a unsigned char* (thanks to…
Chris
- 3
- 2
-1
votes
1 answer
How to add a 8 bytes Hex enumeration value to an unsigned char pointer?
I have this Hexadecimal enumeration of 8 bytes:
enum MyEnum
{
OPTION_1 = 0x000000;
OPTION_2 = 0x000001;
};
Is there any way to add OPTION_1to the following pointer (this pointer will contain other binary data):
unsigned char*…
Farah
- 2,469
- 5
- 31
- 52
-1
votes
1 answer
Why "cout" works weird for "unsigned char"?
I have the following code:
cvtColor (image, image, CV_BGRA2RGB);
Vec3b bottomRGB;
bottomRGB=image.at(821,1232);
When I display bottomRGB[0], it displays a value greater than 255. What is the reason for this?
Khawar Ali
- 3,462
- 4
- 27
- 55
-1
votes
1 answer
Converting string to unsigned char
I've spent a while trying to get a string to turn into an array of unsigned chars, but no luck.
I'm doing an AES implementation and I have everything set up except the input reading part.
This is the code I have ATM.
string text = "E3 FD 51 12" ;
…
inzombiak
- 171
- 2
- 14
-1
votes
2 answers
Add values to char in c?
Hey guys so I have a char and I want to add some integer/double to it. The char must be a signed char, so I can't just make it an int.
char var = -55;
printf("Char is %d, add, char is now: %d\n", var, var+2);
That code works, but as soon as I want…
Travv92
- 791
- 4
- 14
- 27
-2
votes
1 answer
How to convert unsigned long long int into unsigned char*?
Say for instance I have this unsigned long long int:
unsigned long long int test_int = 0xcfffedefcfffeded; // 14987959699154922989
How could I convert test_int into the following unsigned char* array:
unsigned char test_char[] =…
mehmed_ali343
- 9
- 4