| #!/usr/bin/python | |
| # netaddr does this and more: | |
| # >>> import netaddr | |
| # >>> netaddr.EUI('d4:be:d9:23:d5:bf').words | |
| import sys | |
| if len(sys.argv) != 2: | |
| print "usage %s mac-addr" % sys.argv[0] | |
| sys.exit(-1) |
| - Download the toochain from http://buildroot.uclibc.org/downloads/ | |
| Once downloaded & unpacked: | |
| make menuconfig | |
| Then configure the toolchain, check kernel, uclibc, etc versions: | |
| - kernel version (uname -a) | |
| linux 2.6 (manually specified?) | |
| linux version: 2.6.22 | |
| - Kernel & arch: |
| One approximate method is to read /proc/meminfo and check Mapped size (on mine its 52544 kB as of now) | |
| and then check nr_mapped in /proc/vmstat (on mine its 131136 as of now). Finally PAGE_SIZE = Mapped/nr_mapped. | |
| Sometimes this gives you an accurate value (as in the current example I've quoted) | |
| and sometimes its approximate but very close. |
I want to write about why GDB is a great tool for learning C. At least part of the difficulty in learning C is that the language isn’t as interactive as using Python or Ruby.
TL;DR You can kinda use gdb as a repl for c
What’s the smallest possible program we could debug to learn about pointers?
| #include <stdio.h> | |
| void hexDump(char *desc, void *addr, int len) | |
| { | |
| int i; | |
| unsigned char buff[17]; | |
| unsigned char *pc = addr; | |
| // Output description if given. | |
| if (desc != NULL) |
| #include <stdio.h> | |
| #include <sys/socket.h> | |
| #include <linux/netlink.h> | |
| #include <linux/connector.h> | |
| #include <linux/cn_proc.h> | |
| #include <stdlib.h> | |
| #include <errno.h> | |
| struct __attribute__ ((aligned(NLMSG_ALIGNTO))) nlcn_msg { | |
| struct nlmsghdr nl_hdr; |
| /* | |
| $ printf '\1' | od -dAn | |
| Little Endian: 1 | |
| Big Endian: 256 | |
| */ | |
| #include <inttypes.h> | |
| int main(int argc, char ** argv){ | |
| volatile uint32_t i=0x01234567; |
| /* | |
| $ LANG=C gcc -g -Wall -Werror socket.c -o socket | |
| $ ./socket 50.116.14.9 0 | |
| START | |
| 2013-08-27 21:04:47.762757 | |
| socket() | |
| 2013-08-27 21:04:47.762859 | |
| Error : Connect Failed Connection refused | |
| 2013-08-27 21:04:47.956695 |
| Permission is hereby granted, free of charge, to any person obtaining a copy | |
| of this software and associated documentation files (the "Software"), to deal | |
| in the Software without restriction, including without limitation the rights | |
| to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
| copies of the Software, and to permit persons to whom the Software is | |
| furnished to do so, subject to the following conditions: | |
| The above copyright notice and this permission notice shall be included in all | |
| copies or substantial portions of the Software. |
