Converting UINT array of binary data to hex (C Programming)


I've got an array of unsigned int binary characters that I would like to convert to an array of uint hex characters.

is there a standard C function for this or would I need to write one my own (and how could that look like)?

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If I understand you correctly, you have:

  unsigned char cbin[100]; // filled with 100 values

and you want:

  unsigned int ibin[100];   // filled with equivalent 100 values

Then just have a for-loop
  for(int i=0; i<100; ++i) {
     ibin[i] = cbin[i];
here...this link will definitelty help you

the function is itoa, which converts an integer into a string, you can pass the 3rd argument as 16 to get hex values, you'll have to go through the array and convert everything.. use strcat to append each character into a string or char array.

Now that for-loop puts one char binary value into one int value. Perhaps you want to pack 4 char binary values into one int value?

One way:
  unsigned int ibin[25];   // filled with equivalent 25*4 = 100 char values

  for(int i=0; i<25; ++i) {
     memcpy( ibin[i], cbin[4*i], 4 );
That packs it, but is it what you want? There are endian issues to consider.
If you have no endian issues, then you can use a union like this:

union pack{
  unsigned char cbin[100]; // filled with 100 char values
  unsigned int ibin[25];
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   unsigned int a[5] = { 0xAAFFCCDD, 0xBBEEDDCC, 0xCCDDEEFF, 0x55443322, 0x11223344 };
   for(int j=0; j<5; j++){
      char b[10];


if that's what you're looking for.
If you want to convert integers to their hexadecimal representation, the result is text - if that is what you want, you could do that like
#include <stdio.h>

unsigned int numbers[100];
char hex[100][9]; // room for 8 chars and the terminating NULL

// fill 'numbers'

// convert:

for (int i = 0; i < 100; ++i) {

  sprintf(hex[i],"%x",numbers[i]); // '%x' will format as hex

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php-newbieAuthor Commented:
worked for me - thanks!
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