Nmap Development mailing list archives
Re: [PATCH] Dramatically reduce # of fopen()s and fclose()s in nbase_rnd.c
From: Kris Katterjohn <katterjohn () gmail com>
Date: Sat, 16 Dec 2006 10:47:51 -0600
Dmitry V. Levin wrote:
On Fri, Dec 15, 2006 at 11:43:38AM -0600, Kris Katterjohn wrote:This simple patch dramatically reduces the number of fopen()s and fclose()s used when getting random numbers from nbase_rnd.c by keeping the rng device open. Before: # strace nmap -p- localhost 2>&1 | grep 'open("/dev/[au]*random"' | wc 512 3584 31744 After: # strace ./nmap -p- localhost 2>&1 | grep 'open("/dev/[au]*random"' | wc 2 14 124You can also compare "strace -c" output to estimate effect of the change.
Oh cool, thanks. The only problem with trying to compare the difference like this is that fopen() has more "stuff" in it than an open() call. If it's just like the one in K&R (Ch. 8 or 9, I believe), it might not be a big deal, but with what's probably in glibc, for example, it's likely bloated -- or at least "feature-rich" :) Of course I _am_ the one who initially counted the open()s, but I just wanted to see how many times fopen() is called, along with the extra stuff in it. Thanks, Kris Katterjohn _______________________________________________ Sent through the nmap-dev mailing list http://cgi.insecure.org/mailman/listinfo/nmap-dev Archived at http://SecLists.Org
Current thread:
- [PATCH] Dramatically reduce # of fopen()s and fclose()s in nbase_rnd.c Kris Katterjohn (Dec 15)
- Re: [PATCH] Dramatically reduce # of fopen()s and fclose()s in nbase_rnd.c Fyodor (Dec 15)
- Re: [PATCH] Dramatically reduce # of fopen()s and fclose()s in nbase_rnd.c Kris Katterjohn (Dec 15)
- Re: [PATCH] Dramatically reduce # of fopen()s and fclose()s in nbase_rnd.c Dmitry V. Levin (Dec 15)
- Re: [PATCH] Dramatically reduce # of fopen()s and fclose()s in nbase_rnd.c Kris Katterjohn (Dec 16)
- Re: [PATCH] Dramatically reduce # of fopen()s and fclose()s in nbase_rnd.c Fyodor (Dec 15)