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@llj098
llj098 / Makefile
Created December 23, 2010 01:36
a sample tcp server runs in kernel
obj-m += tcp_svr_sample.o
all:
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules
clean:
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clea
@jcxplorer
jcxplorer / uuid.js
Created February 12, 2011 16:58
UUID v4 generator in JavaScript (RFC4122 compliant)
function uuid() {
var uuid = "", i, random;
for (i = 0; i < 32; i++) {
random = Math.random() * 16 | 0;
if (i == 8 || i == 12 || i == 16 || i == 20) {
uuid += "-"
}
uuid += (i == 12 ? 4 : (i == 16 ? (random & 3 | 8) : random)).toString(16);
}
@msantos
msantos / bpf.c
Last active April 2, 2024 18:54
Example of using bpf to capture packets
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <err.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
@karthick18
karthick18 / splice.c
Created September 22, 2011 06:31
An example copy of a file to output file using the splice syscall that avoids copying to/from user space buffers to kernel space by employing pipe buffers allocated in kernel space for fast data transfers between 2 files
/*
* An example using splice syscall which avoids copying to/from user space buffers to kernel space
* and uses the pipe buffers allocated in kernel space as an intermediate to directly xfer from one file to another
*
* gcc -o splice splice.c -g
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
@bellbind
bellbind / ecc.py
Created December 1, 2011 08:08
[python]basics of elliptic curve cryptography
# Basics of Elliptic Curve Cryptography implementation on Python
import collections
def inv(n, q):
"""div on PN modulo a/b mod q as a * inv(b, q) mod q
>>> assert n * inv(n, q) % q == 1
"""
for i in range(q):
if (n * i) % q == 1:
@waylan
waylan / subprocess_pipe.md
Created April 10, 2012 19:12
Writing to a python subprocess pipe

Here's a few things I tried to write output to a python subprocess pipe.

from subprocess import Popen, PIPE

p = Popen('less', stdin=PIPE)
for x in xrange(100):
    p.communicate('Line number %d.\n' % x)
@MohamedAlaa
MohamedAlaa / tmux-cheatsheet.markdown
Last active July 16, 2024 16:59
tmux shortcuts & cheatsheet

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname
@aspyct
aspyct / signal.c
Last active February 19, 2024 11:24
Unix signal handling example in C, SIGINT, SIGALRM, SIGHUP...
/**
* More info?
* a.dotreppe@aspyct.org
* http://aspyct.org
*
* Hope it helps :)
*/
#include <stdio.h>
#include <stdlib.h>
@jikamens
jikamens / encryption.py
Last active August 11, 2017 03:49
Python code for Schematics field encryption / decryption that is compatible with Ruby's mongoid-encrypted-fields + gibberish. The Encryptor object in this gist does encryption / decryption that is compatible with "openssl enc -k *password* -salt -aes-256-cbc". If you want it also to be compatible with mongoid-encrypted-fields, then you need to s…
import binascii
from Crypto.Cipher import AES
from Crypto.Random.random import getrandbits
from hashlib import md5
from schematics.types import StringType
import struct
class DecryptionException(Exception):
pass
@niw
niw / libpng_test.c
Last active June 19, 2024 10:32
How to read and write PNG file using libpng. Covers trivial method calls like png_set_filler.
/*
* A simple libpng example program
* http://zarb.org/~gc/html/libpng.html
*
* Modified by Yoshimasa Niwa to make it much simpler
* and support all defined color_type.
*
* To build, use the next instruction on OS X.
* $ brew install libpng
* $ clang -lz -lpng16 libpng_test.c