I need a hex2str or hex2int function.

Posted on 1998-07-07
Last Modified: 2012-05-04


I am in need of a function to transform hex strings (for ex: "1cf3bei4") to their
equivalent strings or unsigned long int.

Thank you.
Question by:zackeel
  • 2
  • 2
LVL 84

Expert Comment

ID: 1251544
i=strtoul("1cf3bei4",(char **)NULL,16);

Accepted Solution

vladimir_12345 earned 100 total points
ID: 1251545
Hi! It's simple:

#include <stdio.h>

long HexStr2Long(const char* szHexStr)
     unsigned long Result;
     sscanf(szHexStr, "%lx", &Result);
     return Result;

char* HexStr2DecStr(const char* szHexStr, char* szDecStr)
     sprintf(szDecStr, "%ld", HexStr2Long(szHexStr));
     return szDecStr;    


Expert Comment

ID: 1251546
Hi! A little error:
use        unsigned long HexStr2Long(const char* szHexStr)
instead of          long HexStr2Long(const char* szHexStr)

LVL 11

Expert Comment

ID: 1251547
ozo, why do you insist on posting perfectly good answers as comments?
LVL 84

Expert Comment

ID: 1251548
Well, I actually seem to have made a typo of scanf for sscanf,
But I figure it's up to the questioner to determine what's a perfectly good answer,
and I'd rather err on the safe side than have a reputation of posting
perfectly poor comments as answers.
And in this case, I didn't think I could give a complete answer,
not knowing what zackeel meant by «equivalent strings» for "1cf3bei4"

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