nanog mailing list archives
Re: interger to I P address
From: David Champion <dgc () uchicago edu>
Date: Wed, 27 Aug 2008 13:27:06 -0500
Actually, who needs loops for that? ... (unsigned char)(((char*)&i)[3]), (unsigned char)(((char*)&i)[2]), (unsigned char)(((char*)&i)[1]), (unsigned char)(((char*)&i)[0])
Let data structures work for you. #include <stdio.h> main(int argc, char *argv[]) { union { unsigned int i; unsigned char c[4]; } ip; int i = 0; ip.i = 1089055123; /* endian-neutral iteration: */ printf("%d.%d.%d.%d\n", ip.c[i++], ip.c[i++], ip.c[i++], ip.c[i++]); return 0; }
$ bc bc 1.06 Copyright 1991-1994, 1997, 1998, 2000 Free Software Foundation, Inc. This is free software with ABSOLUTELY NO WARRANTY. For details type `warranty'. obase=256 1089055123 064 233 169 147
Curse you with your large number bases. But if you don't do GNU: dc <<EOF [0 sd [d 10 % 48 + Sm ld 1 + sd 10 / d 0 <M] sM lMx [LmP ld 1 - d sd 0 <M] sM lMx ] sN 1089055123 [[.]P] sP 4so [d 256 % Si 256 / lo 1 - dso 0 <O] sO lOx 4so [Li lNx lo 1 - dd so 0 <P 0 <O] sO lOx [ ]P EOF -- -D. dgc () uchicago edu NSIT University of Chicago
Current thread:
- RE: interger to I P address, (continued)
- RE: interger to I P address Matlock, Kenneth L (Aug 27)
- RE: interger to I P address Robert D. Scott (Aug 27)
- Re: interger to I P address Colin Alston (Aug 27)
- Re: interger to I P address Shadow (Aug 27)
- Re: interger to I P address Dave Israel (Aug 27)
- Re: interger to I P address Colin Alston (Aug 27)
- Re: interger to I P address Robert Kisteleki (Aug 27)
- Re: interger to I P address Colin Alston (Aug 27)
- Re: interger to I P address Owen DeLong (Aug 27)
- Re: interger to I P address Scott Doty (Aug 27)
- Re: interger to I P address David Champion (Aug 27)
- Re: interger to I P address Andree Toonk (Aug 27)
- Re: interger to I P address Brian Epstein (Aug 27)
- Re: interger to I P address Michael Holstein (Aug 27)
- Re: interger to I P address Izaac (Aug 27)
- Re: interger to I P address Peter Dambier (Aug 27)
- Re: interger to I P address Gary E. Miller (Aug 27)
- Re: interger to I P address Gary E. Miller (Aug 27)