The Process and IRA Services

• Scheduler will be employed to invoke a service to download the XML offered by treasury.gov and parse interesting data out of it.
• Redis will be used as a cache to store the results of parsing the XML.
• Zato's SimpleIO (SIO) will allow you to expose the same set of information to more than one client, each using a different message format, without any code changes or server restarts.

• Interesting: services should provide a real value that makes potential users pause for a moment and, at least, contemplate using the service in their own applications for their own benefit.
• Reusable: making services modular will allow you to make use of them in circumstances yet unforeseen—to build new, and possibly unexpected, solutions on top of lower-level ones.
• Atomic: a service should have a well defined goal, indivisible from the viewpoint of a service's users, and preferably no functionality should overlap between services.

Laying Out the Services

• Zato's scheduler is configured to invoke a service (update-cache) refreshing the cache once in an hour.
• update-cache, by default, fetches the XML for the current month, but it can be configured to grab data for any date. This allows for reuse of the service in other contexts.
• Client applications use either JSON or simple XML to request long-term rates (get-rate), and responses are produced based on data cached in Redis, making them super-fast. A single SIO Zato service can produce responses in JSON, XML or SOAP. Indeed, the same service can be exposed independently in completely different channels, such as HTTP or AMQP, each using different security definitions and not interrupting the message flow of other channels.

Implementation

• Connect to treasury.gov.
• Download the big XML.
• Find interesting elements containing the business data.
• Store it all in Redis cache.

 1 # Fetch connection by its name
 2 out = self.outgoing.plain_http.get('treasury.gov')
 3
 4 # Build a query string the backend data source expects
 5 query_string = {
 6  '$filter':'month(QUOTE_DATE) eq {} and year(QUOTE_DATE) eq
{}'.format(month, year)
 7 }
 8
 9 # Invoke the backend with query string, fetch 
   # the response as a UTF-8 string
10 # and turn it into an XML object
11 response = out.conn.get(self.cid, query_string)

1 xml = etree.fromstring(response)
2
3 # Look up all XML elements needed (date and rate) using XPath
4 elements = xml.xpath('//m:properties/d:*/text()', 
↪namespaces=NAMESPACES)

 1 for date, rate in elements:
 2
 3   # Create a date object out of string
 4   date = parse(date)
 5
 6   # Build a key for Redis and store the data under it
 7   key = REDIS_KEY_PATTERN.format(
 8       date.year, str(date.month).zfill(2), 
↪str(date.day).zfill(2))
 9   self.kvdb.conn.set(key, rate)
10
12   # Leave a trace of our activity
13   self.logger.info('Key %s set to %s', key, rate)

 1 class GetRate(Service):
 2 """ Returns the real long-term rate for a given date
 3 (defaults to today if no date is given).
 4 """
 5 class SimpleIO:
 6     input_optional = ('year', 'month', 'day')
 7     output_optional = ('rate',)
 8
 9 def handle(self):
10     # Get date needed either from input or current day
11     year, month, day = get_date(self.request.input)
12
13     # Build the key the data is cached under
14     key = REDIS_KEY_PATTERN.format(year, month, day)
15
16     # Assign the result from cache directly to response
17     self.response.payload.rate = self.kvdb.conn.get(key)

• SimpleIO was used—this is a declarative syntax for expressing simple documents that can be serialized to JSON or XML in the current Zato version, with more to come in future releases.
• Nowhere in the service did you have to mention JSON, XML or even HTTP at all. It's all working on a high level of Python objects without specifying any output format or transport method.

Installing Services

• Hot-deployment from the command line.
• Hot-deployment from the browser.
• Adding it to services-sources.txt—you can specify a path to a single module, to a Python package or a Python-dotted name by which to import it.

$ cp linuxjournal.py /opt/zato/server1/pickup-dir
$

INFO - zato.hot-deploy.create:22 - Creating tar archive
INFO - zato.hot-deploy.create:22 - Uploaded package id:[21],
↪payload_name:[linuxjournal.py]

• The server to be deployed was stored in an SQL database, and each server from a cluster was notified of the deployment of new code.
• Each server made a backup of currently deployed services and stored it in the filesystem (by default, there's a circular log of the last 100 backups kept).
• Each server imported the service and made it available for use.

Using the GUI to Configure the Resources Needed

• Scheduler's job to invoke the service updating the cache.
• Outgoing HTTP connection definitions for connecting to treasury.gov.
• HTTP channels for each client—there is no requirement that each client be given a separate channel but doing so allows one to assign different security definitions to each channel without interfering with any other.

Testing It

$ zato service invoke /opt/zato/server1 linuxjournal.update-cache
↪--payload '{}'
(None)
$

INFO - Key linuxjournal:rates:2013:09:03 set to 1.22

$ curl localhost:17010/client1/get-rate -d 
↪'{"year":"2013","month":"09","day":"03"}'
↪{"response": {"rate": "1.22"}}
$

$ curl localhost:17010/client2/get-rate -d '
20130903'


K295602460207582970321705053471448424629
ZATO_OK


1.22


$

$ curl localhost:17010/client3/get-rate \
    -H "SOAPAction:get-rates" -d '



2013
09
03


'





K175546649891418529601921746996004574051
ZATO_OK


1.22




$

IRA Is the Key

• I: focus on providing data interesting to multiple parties.
• R: can take part in many processes and be accessed through more than one method.
• A: focus on one job only and do it well.

• Anti-I: update-cache could be turned into two smaller services. One would fetch data and store it in an SQL database; the other would grab it from SQL and put it into Redis. Even if such a design could be defended by some rationale, neither of the pair of services would be interesting for external applications. A third service wrapping these two should be created and exposed to client apps, in the case of it being necessary for other systems to update the cache. In other words, let's keep the implementation details inside without exposing them to the whole world.
• Anti-R: hard-coding nontrivial parameters is almost always a poor idea. The result being that a service cannot be driven by external systems invoking it with a set of arguments. For instance, creating a service that is limited to a specific year only ensures its limited use outside the original project.
• Anti-A: returning a list of previous queries in response to a request may be a need of one particular client application, but contrary to the needs of another. In cases when a composite service becomes necessary, it should not be obliged upon each and every client.

Born Out of Practical Experience

• Each config file is versioned automaticallyand kept in a local bzr repository, so it's always possible to revert to a safe state. This is completely transparent and needs no configuration nor management.
• A frequent requirement before integration projects are started, particularly if certain services already are available on the platform, is to provide usage examples in the form of message requests and responses. Zato lets you specify that one-in-n invocations of a service be stored for a later use, precisely so that such requirements can be fulfilled by admins quickly.

Summary

-save-temps

• In the first stage, the preprocessor expands all the macros and header files, and strips off comments.
• In the second stage, the compiler acts on the preprocessed code to produce assembly instructions.
• In the third stage, the assembler converts the assembly instructions into machine-level code (object files).
• In the final stage, the linker resolves all the unresolved symbols and combines all the object files to produce an executable.

$ gcc -Wall -save-temps helloworld.c -o helloworld

-Wextra

• Missing parameter type
• Comparison of a pointer with integer zero using >, <, >=, or <=.
• Ambiguous virtual bases

#include

void func(a)
{
    printf("\n func() is passed parameter [%d]\n",a);
    return;
}

int main(void)
{
    printf("\n HELLO \n");
    func(0xFFFFF);

    return 0;
}

$ gcc -Wall -Wextra helloworld.c -o helloworld
helloworld.c: In function 'func':
helloworld.c:4:6: warning: type of 'a' defaults to 'int' [-Wmissing-parameter-type]

#include

void func()
{
    int a = -1;
    int *ptr = &a;

    if(ptr >= 0)
    {
        a = a+1;
    }
    printf("\n a = [%d]\n",a);
    return;
}

int main(void)
{
    printf("\n HELLO \n");
    func();

    return 0;
}

$ gcc -Wall -Wextra helloworld.c -o helloworld
helloworld.c: In function 'func':
helloworld.c:9:12: warning: ordered comparison of pointer with integer zero [-Wextra]

-Wfloat-equal

#include

void func(float a, float b)
{
    printf("\n Inside func() \n");
    if(a == b)
    {
        printf("\n a == b\n");
    }
    return;
}


int main(void)
{
    printf("\n HELLO \n");
    func(1.345, 1.345678);

    return 0;
}

$ gcc -Wfloat-equal helloworld.c -o helloworld
helloworld.c: In function 'func':
helloworld.c:7:10: warning: comparing floating point with == or != is unsafe [-Wfloat-equal]

-g

#include
#include
#include

void func()
{
    char *p = (char*) malloc(10);
    printf("\n Inside func() \n");
    return;
}

int main(void)
{
    printf("\n HELLO \n");
    func();

    return 0;
}

$ valgrind --tool=memcheck --leak-check=yes ./helloworld
==3471== Memcheck, a memory error detector
==3471== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al.
==3471== Using Valgrind-3.8.1 and LibVEX; rerun with -h for copyright info
==3471== Command: ./helloworld
==3471==

 HELLO

 Inside func()
==3471==
==3471== HEAP SUMMARY:
==3471==     in use at exit: 10 bytes in 1 blocks
==3471==   total heap usage: 1 allocs, 0 frees, 10 bytes allocated
==3471==
==3471== 10 bytes in 1 blocks are definitely lost in loss record 1 of 1
==3471==    at 0x4C2CD7B: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==3471==    by 0x40058D: func (in /home/himanshu/practice/helloworld_dir/helloworld)
==3471==    by 0x4005B6: main (in /home/himanshu/practice/helloworld_dir/helloworld)
==3471==
==3471== LEAK SUMMARY:
==3471==    definitely lost: 10 bytes in 1 blocks
==3471==    indirectly lost: 0 bytes in 0 blocks
==3471==      possibly lost: 0 bytes in 0 blocks
==3471==    still reachable: 0 bytes in 0 blocks
==3471==         suppressed: 0 bytes in 0 blocks
==3471==
==3471== For counts of detected and suppressed errors, rerun with: -v
==3471== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 2 from 2)

$ valgrind --tool=memcheck --leak-check=yes ./helloworld
==3517== Memcheck, a memory error detector
==3517== Copyright (C) 2002-2012, and GNU GPL'd, by Julian Seward et al.
==3517== Using Valgrind-3.8.1 and LibVEX; rerun with -h for copyright info
==3517== Command: ./helloworld
==3517==

 HELLO

 Inside func()
==3517==
==3517== HEAP SUMMARY:
==3517==     in use at exit: 10 bytes in 1 blocks
==3517==   total heap usage: 1 allocs, 0 frees, 10 bytes allocated
==3517==
==3517== 10 bytes in 1 blocks are definitely lost in loss record 1 of 1
==3517==    at 0x4C2CD7B: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==3517==    by 0x40058D: func (helloworld.c:7)
==3517==    by 0x4005B6: main (helloworld.c:16)
==3517==
==3517== LEAK SUMMARY:
==3517==    definitely lost: 10 bytes in 1 blocks
==3517==    indirectly lost: 0 bytes in 0 blocks
==3517==      possibly lost: 0 bytes in 0 blocks
==3517==    still reachable: 0 bytes in 0 blocks
==3517==         suppressed: 0 bytes in 0 blocks
==3517==
==3517== For counts of detected and suppressed errors, rerun with: -v
==3517== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 2 from 2)

@file

$ gcc @options helloworld.c -o helloworld

Linux Box Detail:

sshd Server Configuration:

[rahulpanwar@myhost ~]# tail -6 /etc/ssh/sshd_config
#Subsystem sftp /usr/libexec/openssh/sftp-server
Subsystem sftp internal-sftp
Match Group www-hosting
ChrootDirectory %h
ForceCommand internal-sftp
AllowTcpForwarding no

[rahulpanwar@myhost ~]# sudo /etc/init.d/sshd restart

Create Chroot Users:

[rahulpanwar@myhost ~]# sudo mkdir /etc/skel/public_html
[rahulpanwar@myhost ~]# sudo groupadd www-hosting
[rahulpanwar@myhost ~]# sudo useradd -s /sbin/nologin -g www-hosting linuxexplore.com

Setting Permissions:

[rahulpanwar@myhost ~]# sudo chown root:www-hosting /home/linuxexplore.com
[rahulpanwar@myhost ~]# sudo chmod 755 /home/linuxexplore.com

Shell Script to Create Web Hosting Users:

#!/bin/bash
HOSTING_DIR="/etc/skel/public_html"
CHROOT_GRP="www-hosting"
USR_NAME="$1"

[ ! -d "$HOSTING_DIR" ] && mkdir -p $HOSTING_DIR
grep ^"${CHROOT_GRP}:" /etc/group || /usr/sbin/groupadd www-hosting
grep ^"${USR_NAMEP}:" /etc/passwd || /usr/sbin/useradd -s /sbin/nologin -g $CHROO_GRP $USR_NAME
chown root:$CHROOT_GRP /home/$USR_NAME
chmod 755 /home/$USR_NAME

Selinux Configuration:

[rahulpanwar@myhost ~]# sudo setsebool -P ssh_chroot_rw_homedirs on
[rahulpanwar@myhost ~]# sudo restorecon -R /home/$USERNAME

Troubleshooting

sshd[3505]: fatal: bad ownership or modes for chroot directory "/home/linuxexplore.com"

Learn how gprof can help you to identify the performance bottlenecks in your program’s source code

Resources

Step-by-step

gcc -Wall -c sampleCode.c -pg
gcc -Wall sampleCode.o -o sampleCode -pg

gcc -Wall sampleCode.c -o sampleCode -pg

./sampleCode
Count = [1000000000]

ls gmon.out
gmon.out

file gmon.out
gmon.out: GNU prof performance data - version 1

gprof [command-line-options] [executable- file-name] [profiling-data-file-name] > [output-file]

gprof sampleCode gmon.out > prof_output

gcc -Wall -pg -g sampleCode.c -o sampleCode

gprof -A sampleCode gmon.out > prof_ output

gprof -b -Pfunc_a -Qfunc_a sampleCode gmon.out > prof_output

gprof -b -pfunc_a -qfunc_a sampleCode gmon.out > prof_output

wget http://yum.postgresql.org/9.3/redhat/rhel-6-i386/pgdg-centos93-9.3-1.noarch.rpm
rpm -ivH pgdg-centos93-9.3-1.noarch.rpm
yum install postgresql93-devel postgresql93-server postgresql93-contrib

service postgresql-9.3 initdb
Initializing database:                                     [  OK  ]
/etc/init.d/postgresql-9.3 start
Starting postgresql-9.3 service:                           [  OK  ]
su postgres
bash-4.1$ psql
postgres=# create database vehicles;
CREATE DATABASE

postgres=# \c vehicles;
You are now connected to database "vehicles" as user "postgres".
vehicles=# CREATE TABLE cars(id SERIAL PRIMARY KEY NOT NULL, name TEXT NOT NULL, description TEXT NOT NULL);
CREATE TABLE
vehicles=# INSERT INTO cars(name, description) VALUES ('BMW X5', 'Luxury German SUV with front-engine and four-wheel-drive'), ('Mercedes SLR', 'Luxury German grand tourer with front-engine and rear-wheel-drive'), ('Cadillac Escalade', 'Luxury USA SUV with front-engine and rear-wheel-drive or four-wheel-drive'),('Volkswagen Phaeton', 'Luxury German sedan with front-engine and four-wheel drive'), ('Ford Probe', 'USA sports coupe with front-engine and rear-wheel drive'), ('Honda City', 'Japanese compact car with front-engine and front-wheel drive'), ('KIA Sportage', 'South-Korean crossover with front-engine and rear-wheel-drive or four-wheel-drive'),('Skoda Yeti', 'Czech compact SUV with front-engine and front-wheel-drive or four-wheel-drive');
INSERT 0 8
vehicles=# CREATE TABLE engines_manufacturers(id SERIAL PRIMARY KEY NOT NULL, manufacturer_name TEXT NOT NULL);
CREATE TABLE
vehicles=# INSERT INTO engines_manufacturers(manufacturer_name) VALUES ('BMW'),('McLaren'),('GM'),('Mercedes Benz'),('Ford Motor Company'),('VW'),('Hyundai-Kia'),('Peugeot Citroen Moteurs'),('Honda Motor Company');
INSERT 0 9
vehicles=# CREATE TABLE cars_engines(cars_id INT REFERENCES cars NOT NULL, engines_id INT REFERENCES engines_manufacturers NOT NULL, UNIQUE(cars_id,engines_id));
CREATE TABLE
vehicles=# INSERT INTO cars_engines(cars_id,engines_id) VALUES(1,1),(2,2),(3,3),(4,6),(5,5),(6,9),(7,7),(8,6);
INSERT 0 8

Standard string search methods

vehicles=# SELECT name, description FROM cars WHERE description ILIKE '%luxury%suv%';
       name        |                                description
-------------------+---------------------------------------------------------------------------
 BMW X5            | Luxury German SUV with front-engine and four-wheel-drive
 Cadillac Escalade | Luxury USA SUV with front-engine and rear-wheel-drive or four-wheel-drive
(2 rows)

vehicles=# SELECT cars.name as Cars, engines_manufacturers.manufacturer_name as Manufacturer FROM cars INNER JOIN cars_engines ON cars.id = cars_engines.cars_id INNER JOIN engines_manufacturers ON cars_engines.engines_id = engines_manufacturers.id WHERE engines_manufacturers.manufacturer_name ILIKE 'vw' AND cars.description !~* '.*german.*';
    cars    | manufacturer
------------+--------------
 Skoda Yeti | VW
(1 row)

Fuzzy string matching

vehicles=# SELECT id, name FROM cars WHERE levenshtein(name, 'sportage') <=5;
 id |     name
----+--------------
  7 | KIA Sportage
(1 row)
vehicles=# SELECT id, name FROM cars WHERE levenshtein(name, 'sportage') <=4;
 id | name
----+------
(0 rows)
vehicles=# SELECT id, name FROM cars WHERE levenshtein(lower(name), lower('sportage')) <=4;
 id |     name
----+--------------
  7 | KIA Sportage
(1 row)

Trigram

vehicles=# select show_trgm('Ford');
          show_trgm
-----------------------------
 {"  f"," fo",for,ord,"rd "}
(1 row)

vehicles=# CREATE INDEX cars_name_trigram ON cars USING gist(name gist_trgm_ops);
CREATE INDEX

vehicles=# select show_limit();
 show_limit
------------
        0.3
(1 row)
vehicles=# SELECT * FROM cars WHERE name % 'Folkswagen';
 id |        name        |                        description
----+--------------------+------------------------------------------------------------
  4 | Volkswagen Phaeton | Luxury German sedan with front-engine and four-wheel drive
(1 row)
vehicles=# SELECT * FROM cars WHERE name % 'Folkswagon';
 id | name | description
----+------+-------------
(0 rows)
vehicles=# select set_limit(0.2);
 set_limit
-----------
       0.2
(1 row)
vehicles=# SELECT * FROM cars WHERE name % 'Folkswagon';
 id |        name        |                        description
----+--------------------+------------------------------------------------------------
  4 | Volkswagen Phaeton | Luxury German sedan with front-engine and four-wheel drive
(1 row)

TSvector and TSquery

vehicles=# SELECT name, description FROM cars WHERE to_tsvector(description) @@ to_tsquery('english', 'luxury & SUVs');
       name        |                                description
-------------------+---------------------------------------------------------------------------
 BMW X5            | Luxury German SUV with front-engine and four-wheel-drive
 Cadillac Escalade | Luxury USA SUV with front-engine and rear-wheel-drive or four-wheel-drive
(2 rows)

vehicles=# \dFd
                             List of text search dictionaries
   Schema   |      Name       |                        Description
------------+-----------------+-----------------------------------------------------------
 pg_catalog | danish_stem     | snowball stemmer for danish language
 pg_catalog | dutch_stem      | snowball stemmer for dutch language
 pg_catalog | english_stem    | snowball stemmer for english language
 pg_catalog | finnish_stem    | snowball stemmer for finnish language
 pg_catalog | french_stem     | snowball stemmer for french language
 pg_catalog | german_stem     | snowball stemmer for german language
 pg_catalog | hungarian_stem  | snowball stemmer for hungarian language
 pg_catalog | italian_stem    | snowball stemmer for italian language
 pg_catalog | norwegian_stem  | snowball stemmer for norwegian language
 pg_catalog | portuguese_stem | snowball stemmer for portuguese language
 pg_catalog | romanian_stem   | snowball stemmer for romanian language
 pg_catalog | russian_stem    | snowball stemmer for russian language
 pg_catalog | simple          | simple dictionary: just lower case and check for stopword
 pg_catalog | spanish_stem    | snowball stemmer for spanish language
 pg_catalog | swedish_stem    | snowball stemmer for swedish language
 pg_catalog | turkish_stem    | snowball stemmer for turkish language
(16 rows)

vehicles=# CREATE INDEX cars_vector_search ON cars USING gist(to_tsvector('english', description));                          CREATE INDEX

Metaphone

vehicles=# SELECT metaphone('Honda City', 5);
 metaphone
-----------
 HNTST
(1 row)

vehicles=# select manufacturer_name, metaphone(manufacturer_name,11), dmetaphone(manufacturer_name), dmetaphone_alt(manufacturer_name) from engines_manufacturers where engines_manufacturers.id=8;
    manufacturer_name     |  metaphone  | dmetaphone | dmetaphone_alt
-------------------------+-------------+------------+----------------
 Peugeot Citroen Moteurs | PJTSTRNMTRS | PJTS       | PKTS
(1 row)
vehicles=# SELECT manufacturer_name FROM engines_manufacturers WHERE metaphone(engines_manufacturers.manufacturer_name, 2) = metaphone('Pejo', 2);
    manufacturer_name
-------------------------
 Peugeot Citroen Moteurs
(1 row)

SELECT cars.name as Cars, engines_manufacturers.manufacturer_name as Manufacturer FROM cars INNER JOIN cars_engines ON cars.id = cars_engines.cars_id INNER JOIN engines_manufacturers ON cars_engines.engines_id = engines_manufacturers.id WHERE metaphone(engines_manufacturers.manufacturer_name, 6) = metaphone('FW', 6);
        cars        | manufacturer
--------------------+--------------
 Volkswagen Phaeton | VW
 Skoda Yeti         | VW
(2 rows)

What is a job control?

Who provides a facility to control jobs?

Say hello to job table

#1: Creating your first Linux/Unix job

Fig.01: Running the xeyes command in the background

[1] 6891

• [1] : The xeyes job, which was started in the background, was job number 1.
• 6891 : A process ID of job number 1.

## Start a text editor, system load average display for X, and sleepcommand ##
gedit /tmp/hello.c &
xload &
sleep100000&
 

#2: List the current jobs

[1]   9379 Running                 xeyes &
[2]   9380 Running                 gedit /tmp/hello.c &
[3]-  9420 Running                 xload &
[4]+  9421 Running                 sleep 100000 &

#3: Stop or suspend running jobs

kill -s stop PID

Animated gif 01: Suspending ping command job

#4: Resume suspended/stopped job in the foreground

## Job id number 5forpingcommand ##
fg %5

## %String ##
fg %ping

64 bytes from www.cyberciti.biz (75.126.153.206): icmp_req=3 ttl=53 time=265 ms
64 bytes from www.cyberciti.biz (75.126.153.206): icmp_req=4 ttl=53 time=249 ms
64 bytes from www.cyberciti.biz (75.126.153.206): icmp_req=5 ttl=53 time=267 ms
^C

#5: Resume suspended/stopped job in the background

[7]+  Stopped                 yum -y update &>/root/patch.log &

Restart a stopped background yum process with bg

[7]+ yum -y update &>/root/patch.log &

#6: Kill a job / process

[7]+  Terminated              yum -y update &>/root/patch.log &

#7 Why does shell kill off all my background jobs when I logout?

 
~/scripts/www/pdfwriter.py --profile=faq --type=clean --header=logo\
--footer-left "nixCraft is GIT UL++++ W+++ C++++ M+ e+++ d-" \
--footer-right "Page [of] of [total]"&
 

#8 Prevent job from being killed on logout using an external command called nohup

#9: Finding the PID of last job

PID of most recently executed background job - 9421

#10: Wait for job completion

 
/path/to/large-job/command/foo &
wait $!
/path/to/next/job/that-is-dependents/on-foo-command/bar
 

#!/bin/bash
# A shell script wrapper to create pdf files for our blog/faq section
########################################################################
# init() - Must be run first 
# Purpose - Create index filein$_tmpfor all our wordpress databases 
########################################################################
init(){
_php="/usr/bin/php"
_phpargs="-d apc.enabled=0"
_base="~/scripts"
_tmp="$_base/tmp"
_what="$1"
for i in$_what
do
[[ ! -d "$_tmp/$i"]]&& /bin/mkdir"$_tmp/$i"
$_php$_phpargs -f "$_base/php/rawsqlmaster${i}.php">  "$_tmp/$i/output.txt"
done
}
 
#####################################################
# Without index file, we can out generate pdf files
#####################################################
init blog
 
###########################################################
# Do not run the rest of the script until init() finished
###########################################################
wait $!
 
## Alright, create pdf files 
~/scripts/www/pdfwriter.py --profile=blog --type=clean --header=logo\
--footer-left "nixCraft is GIT UL++++ W+++ C++++ M+ e+++ d-" \
--footer-right "Page [of] of [total]"
 

Linux and Unix job control command list summery

A note about shell built-in and external commands

 
type -a fgbgjobsdisown
 

fg is a shell builtin
fg is /usr/bin/fg
bg is a shell builtin
bg is /usr/bin/bg
jobs is a shell builtin
jobs is /usr/bin/jobs
disown is a shell builtin

Conclusion

• See our faq section for disown command examples, jobs command examples, bg command examples, and fg command examples on Linux/Unix process management.
• Man pages - bash(1), ksh(1), ps(1), kill(1)
• Korn shell (ksh93) documentation.
• GNU bash shell documentation.

ServerAliveInterval 60

ServerAliveCountMax 10

TCPKeepAlive no

ControlMaster auto
ControlPath ~/.ssh/%r@%h:%p
ControlPersist 4h

cd voicememo
cordova platform add android

The home page of the VoiceMemo application, which represents the list of voice memos.

• Media Capture plugin, for media capture:
  cordova plugin add https://git-wip-us.apache.org/repos/asf/cordova-plugin-media-capture.git
• Media plugin, for working with media:
  cordova plugin add https://git-wip-us.apache.org/repos/asf/cordova-plugin-media.git
• Device plugin, for accessing device information:
  cordova plugin add https://git-wip-us.apache.org/repos/asf/cordova-plugin-device.git
• Dialog plugin, for displaying native-looking messages:
  cordova plugin add https://git-wip-us.apache.org/repos/asf/cordova-plugin-dialogs.git
• File plugin, for accessing the mobile filesystem:
  cordova plugin add https://git-wip-us.apache.org/repos/asf/cordova-plugin-file.git

• css contains the custom application Cascading Style Sheet.
• jqueryMobile contains the jQuery Mobile framework and plugins JStorage and Page Params.
• js contains all the custom application JavaScript code. It has three subdirectories:
  • api contains the application managers (VoiceManager and CacheManager) and utility files.
  • model contains the application model. In this application we have a single object that represents a Voice item called VoiceItem.
  • vc contains the application view controllers, which include the application action handlers. Action handlers usually create model objects and populate them with UI data, pass them to the application APIs, and display the results on the application view or page.

• Voice Listing (home page)
• Voice Recording
• About

About

Memo List

New







Remove All Memos

(function() {

    var voiceManager = VoiceManager.getInstance();

    $(document).on("pageinit", "#voiceList", function(e) {

     $("#removeAllVoices").on("tap", function() {
      e.preventDefault();

      voiceManager.removeAllVoices();

      updateVoiceList();
     });      
    });

    $(document).on("pageshow", "#voiceList", function(e) {
        e.preventDefault();

        updateVoiceList();
    });

    function updateVoiceList() {
        var voices = voiceManager.getVoices();

        $("#voiceListView").empty();

        if (jQuery.isEmptyObject(voices)) {
            $("

Home

Record Voice

Back





Title



Description



Recording

(function() {

    var voiceManager = VoiceManager.getInstance();

    $(document).on("pageinit", "#voiceRecording", function(e) {
        e.preventDefault();

        $("#saveVoice").on("tap", function() {
            e.preventDefault();

            var voiceItem = new VoiceItem($("#title").val() || "Untitled", 
                                          $("#desc").val() || "", 
                                          $("#location").val() || "",
                                          $("#vid").val() || null);

            voiceManager.saveVoice(voiceItem);

            $.mobile.changePage("#voiceList");
        });        

        $("#recordVoice").on("tap", function() {
            e.preventDefault();

            var recordingCallback = {};

            recordingCallback.captureSuccess = handleCaptureSuccess;
            recordingCallback.captureError = handleCaptureError;

            voiceManager.recordVoice(recordingCallback);
         }); 

        $("#playVoice").on("tap", function() {
            e.preventDefault();

            var playCallback = {};

            playCallback.playSuccess = handlePlaySuccess;
            playCallback.playError = handlePlayError;

            voiceManager.playVoice($("#location").val(), playCallback);
        });           

    });

    $(document).on("pageshow", "#voiceRecording", function(e) {
        e.preventDefault();

        var voiceID = ($.mobile.pageData && $.mobile.pageData.voiceID) ? $.mobile.pageData.voiceID : null;
        var voiceItem = new VoiceItem("", "", "");

        if (voiceID) {

            //Update an existing voice
            voiceItem = voiceManager.getVoiceDetails(voiceID);
        } 

        populateRecordingFields(voiceItem);

        if (voiceItem.location.length > 0) {
            $("#playVoice").closest('.ui-btn').show();
        } else {
            $("#playVoice").closest('.ui-btn').hide();    
        }        
    });

    $(document).on("pagebeforehide", "#voiceRecording", function(e) {
        voiceManager.cleanUpResources();
    });

    function populateRecordingFields(voiceItem) {
        $("#vid").val(voiceItem.id);
        $("#title").val(voiceItem.title);
        $("#desc").val(voiceItem.desc);
        $("#location").val(voiceItem.location);
    }

    function handleCaptureSuccess(mediaFiles) {
        if (mediaFiles && mediaFiles[0]) {        
            currentFilePath = mediaFiles[0].fullPath;

            $("#location").val(currentFilePath);

            $("#playVoice").closest('.ui-btn').show();  
        }
    }

    function handleCaptureError(error) {
     displayMediaError(error);
    }  

    function handlePlaySuccess() {
        console.log("Voice file is played successfully ...");
    }

    function handlePlayError(error) {
     displayMediaError(error);
    }        

    function displayMediaError(error) {
        if (error.code == MediaError.MEDIA_ERR_ABORTED) {
            AppUtil.showMessage("Media aborted error");
        } else if (error.code == MediaError.MEDIA_ERR_NETWORK) {
            AppUtil.showMessage("Network error");
        } else if (error.code == MediaError.MEDIA_ERR_DECODE) {
            AppUtil.showMessage("Decode error");
        } else if (error.code ==  MediaError.MEDIA_ERR_NONE_SUPPORTED) {
            AppUtil.showMessage("Media is not supported error");
        } else {
         console.log("General Error: code = " + error.code);
        }        
    }
})();

About

Memo List

New







Remove All Memos





Home

Record Voice

Back





Title



Description



Recording











Home

About

Back


                This sample is developed for education purposes

var VoiceManager = (function () {     
  var instance;

  function createObject() {
      var cacheManager = CacheManager.getInstance();
      var VOICES_KEY = "voices";
      var voiceMap;
      var audioMedia;

      return {
          getVoices: function () {
              voiceMap = cacheManager.get(VOICES_KEY) || {};

              return voiceMap;
          }, 
          getVoiceDetails: function (voiceID) {
              voiceMap = cacheManager.get(VOICES_KEY) || {};

              return voiceMap[voiceID];
          },
          saveVoice: function (voiceItem) {  
              voiceMap = cacheManager.get(VOICES_KEY) || {};

              voiceMap[voiceItem.id] = voiceItem;

              cacheManager.put(VOICES_KEY, voiceMap);
          }, 
          removeAllVoices: function() {
              cacheManager.remove(VOICES_KEY);
          },
          recordVoice: function (recordingCallback) {
              navigator.device.capture.captureAudio(recordingCallback.captureSuccess, 
                                                    recordingCallback.captureError, 
                                                    {limit: 1});
          }, 
          playVoice: function (filePath, playCallback) {
              if (filePath) {

               //You have to make this in order to make this working on Android ...
                  filePath = filePath.replace("file:/","file://");

               this.cleanUpResources();

               audioMedia = new Media(filePath, playCallback.playSuccess, playCallback.playError);

               // Play audio
               audioMedia.play();
              }            
          }, 
          cleanUpResources: function() {
              if (audioMedia) {
               audioMedia.stop();
                  audioMedia.release();
                  audioMedia = null;
              } 
          }
    };
  };

  return {
    getInstance: function () {
      if (!instance) {
          instance = createObject();
      }

      return instance;
    }
  }; 
})();

var CacheManager = (function () {     
  var instance;

  function createObject() {   
    return {
        put: function (key, value) {
            $.jStorage.set(key, value);
        },
        get: function (key) {
         return $.jStorage.get(key);
        },
        remove: function (key) {
         return $.jStorage.deleteKey(key);
        }
    };
  };

  return {
    getInstance: function () {

      if (!instance) {
        instance = createObject();
      }

      return instance;
    }
  }; 
})();

var VoiceItem = function(title, desc, location, id) {
 this.title = title || "";
 this.desc = desc || "";
 this.location = location || "";
 this.id = id || "Voice_" + (new Date()).getTime();
};

VoiceItem.prototype.toString = function () {
 return "Title = " + this.title + ", " +
"Description = " + this.desc + ", " +
"Location = " + this.location + ", " +
"ID = " + this.id;
};

Conclusion

Today in Open Source: DuckDuckGo gains more users as privacy concerns mount. Plus: An exhaustive list of Open Source software, and the Ubuntu phone may be delayed until 2015

DuckDuckGo reported phenomenal growth last year, and it's no wonder.
In a time when our privacy is continually being eroded, and every day there seems to be a new revelation about government surveillance, many people are looking away from major search engines like Google and Bing and moving to DuckDuckGo, a service that guarantees it doesn't save your search information.

Image credit: Fierce Content Management
More at Fierce Content Management

Image credit: DuckDuckGo

For the fifth year in a row, Datamation is closing out the year with a big, big list of all the software we've featured on our monthly open source software guides. This year's list is the longest ever with 1,180 projects in 143 different categories from Accessibility to Wine and Beer.
We refreshed the list with all the new applications we've highlighted this year, and we dropped those that hadn't been updated in a while. Please note that the list is organized by category and alphabetically within each category — the numbers don't indicate rank or quality.
More at Datamation

When Canonical CEO Jane Silber first announced plans to port Ubuntu to phones last year, she said the goal was to ship the first handsets with the OS preloaded by the end of 2013.
That didn't happen, and from the sound of it, Ubuntu fans probably shouldn't hold their breath for a dedicated Ubuntu phone this year, either. Even if one does appear, it will likely be a limited-run device targeting niche use cases.
"Longer-term we would love to see the major OEM/Carriers shipping Ubuntu handsets," Ubuntu community manager Jono Bacon wrote in a recent Reddit AMA session. "This is a long road though with many components, and I would be surprised if we see anything like this before 2015."
More at The Register

How to install mod_cluster

LoadModule slotmem_module modules/mod_slotmem.so
LoadModule manager_module modules/mod_manager.so
LoadModule proxy_cluster_module modules/mod_proxy_cluster.so

Listen 192.168.204.203:9999




        Order deny,allow
        Allow from all 192.168


    ManagerBalancerName mymodcluster
    EnableMCPMReceive


ProxyPass / balancer://mymodcluster/

How to set up Tomcat for mod_cluster

Dec 23, 2013 8:34:00 AM org.jboss.modcluster.ModClusterService init
INFO: MODCLUSTER000001: Initializing mod_cluster ${project.version}
Dec 23, 2013 8:34:11 AM org.jboss.modcluster.ModClusterService connectionEstablished
INFO: MODCLUSTER000012: Catalina connector will use /192.168.204.204

[Mon Dec 23 08:36:22 2013] [debug] proxy_util.c(2026): proxy: ajp: has acquired connection for (192.168.204.204)
[Mon Dec 23 08:36:22 2013] [debug] proxy_util.c(2082): proxy: connecting ajp://192.168.204.204:8009/ to 192.168.204.204:8009
[Mon Dec 23 08:36:22 2013] [debug] proxy_util.c(2209): proxy: connected / to 192.168.204.204:8009
[Mon Dec 23 08:36:22 2013] [debug] mod_proxy_cluster.c(1366): proxy_cluster_try_pingpong: connected to backend
[Mon Dec 23 08:36:22 2013] [debug] mod_proxy_cluster.c(1089): ajp_cping_cpong: Done
[Mon Dec 23 08:36:22 2013] [debug] proxy_util.c(2044): proxy: ajp: has released connection for (192.168.204.204)

Preparation

Prevent Reusing Old Passwords

password     [success=1 default=ignore]    pam_unix.so obscure sha512 remember=5

password   sufficient   pam_unix.so sha512 shadow nullok try_first_pass use_authtok remember=5

Set Minimum Password Length

password   requisite    pam_cracklib.so retry=3 minlen=10 difok=3

password   requisite   pam_cracklib.so retry=3 difok=3 minlen=10

Set Password Complexity

password   requisite    pam_cracklib.so retry=3 minlen=10 difok=3 ucredit=-1 lcredit=-2 dcredit=-1 ocredit=-1

password   requisite   pam_cracklib.so retry=3 difok=3 minlen=10 ucredit=-1 lcredit=-2 dcredit=-1 ocredit=-1

Set Password Expiration Period

PASS_MAX_DAYS   150
PASS_MIN_DAYS   0
PASS_WARN_AGE   7

Last password change                                    : Dec 30, 2013
Password expires                                        : never
Password inactive                                       : never
Account expires                                         : never
Minimum number of days between password change          : 0
Maximum number of days between password change          : 99999
Number of days of warning before password expires       : 7

There are times when you are stuck using a locked-down machine. As long as you have a browser, though, you can still connect to your remote machines. Here’s how…

Resources

Install CutyCapt on Linux

Install CutyCapt on Debian, Ubuntu or Linux Mint

Install CutyCapt on Fedora

#include 
#include 

Install CutyCapt on CentOS or RHEL

Convert HTML to PNG with CutyCapt

Convert HTML to PNG with CutyCapt on a Headless Server

cutycapt: cannot connect to X server :0

Conditional breakpoints

#include 

int main()
{
    int num = -1;
    int total = -1;
    int count = 0;
    int values[] = {10, 256, 55, 67, 43, 89, 78, 78, 89, 0};

    while(count < 10)
    {
            num = values[count];
            total = num + 0xffffffff/num;

            printf("\n result = [%d]\n", total);
            count++;
    }

    return 0;
}

$ gdb test
GNU gdb (GDB) 7.6.1-ubuntu
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later 
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "i686-linux-gnu".
For bug reporting instructions, please see:
...
Reading symbols from /home/himanshu/practice/wazi/gdb/test...done.
(gdb) break 13 if num==0
Breakpoint 1 at 0x804849c: file test.c, line 13.
(gdb) run
Starting program: /home/himanshu/practice/wazi/gdb/test

 result = [429496739]

 result = [16777471]

 result = [78090369]

 result = [64104056]

 result = [99883003]

Breakpoint 1, main () at test.c:13
13                total = num + 0xffffffff/num;
(gdb) n

Program received signal SIGFPE, Arithmetic exception.
0x080484aa in main () at test.c:13
13                total = num + 0xffffffff/num;
(gdb)

Ignore breakpoints

#include 

int main()
{
    int num = -1;
    int total = -1;
    int count = 50;

    while(count--)
    {
        // a lot of code here

        total = num + 0xffffffff/(count-10);
        printf("\n result = [%d]\n", total);

            // a lot of code here
    }

    return 0;
}

$ gdb -q test
Reading symbols from /home/himanshu/practice/wazi/gdb/test...done.
(gdb) break 10
Breakpoint 1 at 0x8048440: file test.c, line 10.
(gdb) info breakpoints
Num     Type           Disp Enb Address    What
1       breakpoint     keep y   0x08048440 in main at test.c:10
(gdb) ignore 1 50
Will ignore next 50 crossings of breakpoint 1.
(gdb) run
Starting program: /home/himanshu/practice/wazi/gdb/test

 result = [110127365]

 result = [113025454]

 result = [116080196]

...
...
...

 result = [2147483646]

 result = [-2]

Program received signal SIGFPE, Arithmetic exception.
0x08048453 in main () at test.c:13
13            total = num + 0xffffffff/(count-10);
(gdb) info break 1
Num     Type           Disp Enb Address    What
1       breakpoint     keep y   0x08048440 in main at test.c:10
breakpoint already hit 40 times
    ignore next 10 hits
(gdb)

Use watchpoints

#include 

void func5(int *ptr)
{
    // a lot of code here
    *ptr = 512;
}

void func4(int *ptr)
{
    // a lot of code here
    func5(ptr);
}

void func3(int *ptr)
{
    // a lot of code here
    func4(ptr);
}

void func2(int *ptr)
{
    // a lot of code here
    func3(ptr);
}

void func1(int *ptr)
{
    // a lot of code here
    func2(ptr);
}

int main()
{
    int ref_val = 256;

    func1(&ref_val);

    printf("\n ref_val = [%d]\n", ref_val);

    return 0;
}

$ gdb -q test
Reading symbols from /home/himanshu/practice/wazi/gdb/test...done.
(gdb) break test.c:func5
Breakpoint 1 at 0x8048420: file test.c, line 6.
(gdb) run
Starting program: /home/himanshu/practice/wazi/gdb/test

Breakpoint 1, func5 (ptr=0xbffff0bc) at test.c:6
6        *ptr = 512;
(gdb) watch *ptr
Hardware watchpoint 2: *ptr
(gdb) c
Continuing.
Hardware watchpoint 2: *ptr

Old value = 256
New value = 512
func5 (ptr=0xbffff0bc) at test.c:7
7    }
(gdb)

Call user-defined or system functions

#include 

unsigned int user_defined_strlen(char *ptr)
{
    int len = 0;
    printf("\n User-defined strlen() function called with string [%s]\n", ptr);

    if(NULL == ptr)
    {
        printf("\n Invalid string\n");
        return 0;
    }

    while(*(ptr++) != '\0')
        len++;

    printf("\n[%u]\n", len);
    return len;
}

int main()
{
    char *ptr = "some-string";

    user_defined_strlen(ptr);

    return 0;
}

$ gdb -q test
Reading symbols from /home/himanshu/practice/wazi/gdb/test...done.
(gdb) break test.c:main
Breakpoint 1 at 0x80484bd: file test.c, line 23.
(gdb) run
Starting program: /home/himanshu/practice/wazi/gdb/test

Breakpoint 1, main () at test.c:23
23        char *ptr = "some-string";
(gdb) call user_defined_strlen("wazi")

 User-defined strlen() function called with string [wazi]

[4]
$1 = 4
(gdb)

(gdb) call strlen("wazi")
$2 = 4
(gdb)

Auto-display variable values

$ gdb -q test
Reading symbols from /home/himanshu/practice/wazi/gdb/test...done.
(gdb) break 14
Breakpoint 1 at 0x8048486: file test.c, line 14.
(gdb) run
Starting program: /home/himanshu/practice/wazi/gdb/test

 User-defined strlen() function called with string [some-string]

Breakpoint 1, user_defined_strlen (ptr=0x80485c2 "some-string") at test.c:14
14        while(*(ptr++) != '\0')
(gdb) display len
1: len = 0
(gdb) n
15            len++;
1: len = 0
(gdb) n
14        while(*(ptr++) != '\0')
1: len = 1
(gdb) n
15            len++;
1: len = 1
(gdb) n
14        while(*(ptr++) != '\0')
1: len = 2
(gdb) n
15            len++;
1: len = 2
(gdb) n
14        while(*(ptr++) != '\0')
1: len = 3
(gdb) n
15            len++;
1: len = 3
(gdb) n
14        while(*(ptr++) != '\0')
1: len = 4
(gdb) n
15            len++;
1: len = n
(gdb) n
14        while(*(ptr++) != '\0')
1: len = 5
(gdb) n
15            len++;
1: len = 5

(gdb) info display
Auto-display expressions now in effect:
Num Enb Expression
1:   y  len
(gdb) undisplay 1
(gdb) n
15            len++;
(gdb) n
14        while(*(ptr++) != '\0')
(gdb) n
15            len++;
(gdb) n
14        while(*(ptr++) != '\0')
(gdb) n
15            len++;

In conclusion

1. Avidemux

• License: GNU GPL
• Cross-platform (Linux, BSD, MacOS X, Windows)
• Supports both GUI and command-line modes
• Support for JavaScript (thanks to SpiderMonky JavaScript engine)
• Built-in subtitle processing
• Official website: http://fixounet.free.fr/avidemux

2. Cinelerra-CV

• License: GNU GPL
• Community edition of Cinelerra video editor.
• Support for video compositing.
• Drag and drop files from file manager.
• OpenGL-driven GPU acceleration for video playback.
• Video/audio effects and transitions.
• Direct capture from camcorders.
• Cross-platform (Linux and Windows).
• Official website: http://cinelerra.org

3. Flowblade

• License: GNU GPL v3
• Support for multiple file types based on FFmpeg
• Drag and drop files from file manager
• Support for video and image compositing
• Image and audio effects
• Automatic clip placement on the timeline
• Official website: https://code.google.com/p/flowblade/

4. Jahshaka

• License: GNU GPL
• Cross-platform (Linux, MacOS X, Windows)
• Support for 2D/3D animation effects and video composting
• Support for collaborative editing (e.g., editing server and centralized database)
• Media/asset management
• GPU based effects
• Official website: http://www.jahshaka.com

5. Kdenlive

• License: GNU GPL v2+
• Video editor for the KDE desktop
• Support for multiple file types based on FFmpeg
• Video/audio effects and transitions
• Ability ot mix video, audio and still images from different sources
• Video capture from cameras, webcams, Video4Linux devices or X11 screen
• Export to Internet video sharing sites such as YouTube, Dailymotion or Vimeo
• Official website: http://www.kdenlive.org

6. Lightworks

• License: Freemium
• Cross-platform (Linux, BSD, MacOS X, Windows)
• Multi-language support
• GPU-accelerated real-time video effects and composting
• Official website: http://www.lwks.com

7. LiVES

• License: GNU GPL
• Cross-platform (Linux, BSD, MacOS X, Solaris)
• Multi video formats via mplayer
• Extendable video/audio effects via plugins
• Support for remote control via OSC protocol
• Video capture from FireWire cameras and TV cards
• Lossless backup and crash recovery
• Support for clip import from YouTube
• Official website: http://lives.sourceforge.net

8. OpenShot

• License: GNU GPL v3
• Support for multiple file types based on FFmpeg
• Drag and drop files from file manager
• Support for 2D titles (thanks to Inkscape) and 3D-animated titles (thanks to Blender)
• Digital zooming
• Animated video transition with preview
• Support for video compositing and watermark images
• Scrolling eding credits or texts
• Official website: http://www.openshot.org

9. Pitivi

• License: GNU LGPL
• Video import, conversion and rendering powered by GStreamer Editing Service
• Video/audio effects and transitions
• Detachable UI
• Multi-language support (thanks to GNOME integration)
• Official website: http://www.pitivi.org

10. Shotcut

• License: GNU GPL
• Cross-platform (Linux, MacOS X, Windows)
• Support for multiple file types based on FFmpeg
• Customizable UI via dockable panels
• Multi-format timeline (e.g., with different resolutions and frame rates)
• Video capture from webcam, HDMI, IP streams and X11 screen
• Drag and drop files from file manager
• GPU-assisted image processing with OpenGL
• Official website: http://www.shotcut.org

• Set your web server to compress (zip) all of its output.
• Minify your JavaScript code, to yield a shorter but equivalent version.
• Clean up your CSS rules and HTML code and remove unnecessary contents.

Deflate your output

> wget -S -nv -O wazi.html www.openlogic.com/wazi
  HTTP/1.1 200 OK
  Cache-Control: private
  Content-Type: text/html; charset=utf-8
  Server: Microsoft-IIS/7.5
  X-AspNet-Version: 2.0.50727
  X-Powered-By: ASP.NET
  Date: Sun, 16 Feb 2014 00:45:24 GMT
  Transfer-Encoding:  chunked
  Connection: keep-alive
  Connection: Transfer-Encoding
2014-02-15 22:45:24 URL:http://www.openlogic.com/wazi [76250] -> "wazi.html" [1]

> wget -S -nv -O wazi.compressed --header "Accept-Encoding: gzip, deflate, compress" www.openlogic.com/wazi
  HTTP/1.1 200 OK
  Cache-Control: private
  Content-Type: text/html; charset=utf-8
  Server: Microsoft-IIS/7.5
  X-AspNet-Version: 2.0.50727
  X-Powered-By: ASP.NET
  Vary: Accept-Encoding
  Content-Encoding: gzip
  Content-Length: 14315
  Date: Sun, 16 Feb 2014 00:46:10 GMT
  Connection: keep-alive
2014-02-15 22:46:10 URL:http://www.openlogic.com/wazi [14315/14315] -> "wazi.compressed" [1]

  AddOutputFilterByType DEFLATE application/javascript 
  AddOutputFilterByType DEFLATE application/rss+xml 
  AddOutputFilterByType DEFLATE application/x-javascript
  AddOutputFilterByType DEFLATE application/xml 
  AddOutputFilterByType DEFLATE application/xhtml+xml
  AddOutputFilterByType DEFLATE text/css 
  AddOutputFilterByType DEFLATE text/html 
  AddOutputFilterByType DEFLATE text/javascript
  AddOutputFilterByType DEFLATE text/plain 
  AddOutputFilterByType DEFLATE text/richtext
  AddOutputFilterByType DEFLATE text/x-component 
  AddOutputFilterByType DEFLATE text/xsd 
  AddOutputFilterByType DEFLATE text/xsl 
  AddOutputFilterByType DEFLATE text/xml 
  AddOutputFilterByType DEFLATE image/svg+xml 
  AddOutputFilterByType DEFLATE image/x-icon

Minify your JavaScript

/*!
 * jQuery JavaScript Library v2.1.0
 * http://jquery.com/
 *
 * Includes Sizzle.js
 * http://sizzlejs.com/
 *
 * Copyright 2005, 2014 jQuery Foundation, Inc. and other contributors
 * Released under the MIT license
 * http://jquery.org/license
 *
 * Date: 2014-01-23T21:10Z
 */
(function(b,a){if(typeof module==="object"&&typeof module.exports==="object"){module.exports=b.document?a(b,true):function(c){if(!c.document){throw new Error("jQuery requires a window with a document")}
return a(c)}}else{a(b)}}(typeof window!=="undefined"?window:this,function(window,noGlobal){var arr=[];var slice=arr.slice;var concat=arr.concat;var push=arr.push;var indexOf=arr.indexOf;var class2type={
};var toString=class2type.toString;var hasOwn=class2type.hasOwnProperty;var trim="".trim;var support={};var document=window.document,version="2.1.0",jQuery=function(selector,context){return new jQuery.f
n.init(selector,context)},rmsPrefix=/^-ms-/,rdashAlpha=/-([\da-z])/gi,fcamelCase=function(all,letter){return letter.toUpperCase()};jQuery.fn=jQuery.prototype={jquery:version,constructor:jQuery,selector:
"",length:0,toArray:function(){return slice.call(this)},get:function(num){return num!=null?(num<0 args="" arguments="" callback.call="" callback="" e="" each:function="" elem="" elems="" first:function="" function="" i="" j="" jquery.each="" jquery.map="" last:function="" len="this.length,j=+i+(i<0?len:0);return" map:function="" num="" onstructor="" pushstack:function="" q:function="" ret.prevobject="this;ret.context=this.context;return" ret="" return="" slice.apply="" slice.call="" slice:function="" this.eq="" this.length="" this.pushstack="" this="" var="">=0&&j







Three online JavaScript minifying service alternatives
The javascript-minifier
 page lets you paste your code and get a minified alternative; for a 
command-line process you can also invoke it as a web service, through a 
POST request. Packer is another online alternative, which you can also use as a PHP, Perl, or .NET application. And jscompress is based upon both Packer and JSMin, an old tool by Douglas Crockford.



Note that comments starting with /*! are kept, so 
copyright and license texts won't be taken out. (Other compressors may 
not make that distinction, and may take out all comments, whatever their
 origin.) The produced code is more compact than the original, and if it
 were further compressed by Apache as we saw earlier, it would go down 
to about 30K, which is just an eighth of the original size.


We'll revisit YUI Compressor again when we consider how to compress 
CSS, but let's now look at another compressor that offers even more 
options and code trimming.


Google's Closure
 is in fact more than a minifier, because it not only removes extra 
white space, line end characters, and the like, it also revises your 
JavaScript code into better JavaScript by analyzing your code, removing 
useless bits, and rewriting whatever's left into a smaller, tighter, 
more efficient version. As an extra, it warns about possible JavaScript 
problems. You can use Closure as a web service or a RESTful API, but I 
went with a command-line Java jar version. The latest version is dated 1/10/2014, so it's quite up-to-date.


Closure has far too many options to list; after unzipping your download, run java -jar compiler.jar --help to check them out. Working again with the jQuery source code, I ran java
 -jar compiler.jar --compilation_level ADVANCED_OPTIMIZATIONS --js 
jquery-2.1.0.js --js_output_file=jquery.closure.advanced.js and 
got a file of about 75K, which is smaller than jQuery's own minified 
version. Here is a sample of the code. Notice that it is even harder to 
understand than the YUI Compressor version; in advanced compilation 
mode, Closure changes variable and function names, inlines code, and 
performs several optimizations that go beyond minifying.


(function(q,W){"object"===typeof module&&"object"===typeof module.jc?module.jc=q.document?W(q,!0):function(q){if(!q.document)throw Error("jQuery requires a window with a document");return W(q)}:W(q)})("
undefined"!==typeof window?window:this,function(q,W){function ka(a){return a.ownerDocument.defaultView.getComputedStyle(a,null)}function X(a,b){a=b||a;return"none"===d.c(a,"display")||!d.contains(a.owne
rDocument,a)}function Gb(a,b){return b.toUpperCase()}function d(a,b){return new d.b.la(a,b)}function Ba(a){var b=
a.length,c=d.type(a);return"function"===c||d.N(a)?!1:1===a.nodeType&&b?!0:"array"===c||0===b||"number"===typeof b&&0")).ob(b.documentEle
ment),b=T[0].contentDocument,b.write(),b.close(),c=Wa(a,b),T.detach()),Ya[a]=c);return c}function U(a,b,c){var f,e,g=a.style;(c=c||ka(a))&&(e=c.getPropertyValue(b)||c[b]);c&&(""!==e||d.contains(a.ownerDoc [...]
By employing this kind of tool, your development team can work with  clear, fully commented and indented versions of your source code, while  end users get a much shorter version that's optimized for speed – a  win-win situation!
Compress CSS and HTML
Your website consists not only of JavaScript, but also CSS rules and  HTML code, so to round things out let's see how to compress such  content. YUI Compressor, which we already looked at for JavaScript, can  work with CSS files too. I got one of OpenLogic's own CSS files, which  is 22K in size and about 1,400 lines long, and ran java -jar yuicompressor-2.4.8.jar wazi.css -o wazi.yui.css. That got the file down to 17K, a 25% size reduction, in a single extra long line.
.PreviewPanel{border-right:silver thin solid;border-top:silver thin solid;border-left:silver thin solid;border-bottom:silver thin solid}.linksubmission{border:solid 0 red;font:normal 11px Tahoma,Arial,V
erdana,sans-serif}.linksubmission IMG{border:solid 0 red !important}.linksubmission A{border:solid 0 red !important;text-decoration:none !important;font:normal 11px Tahoma,Arial,Verdana,sans-serif}.Grid
Header_Monochrome a:visited,.GridHeader_Monochrome a:hover{color:white !important;font:bold 11px Tahoma !important}.GridPager_Monochrome a:visited,.GridPager_Monochrome a:hover{font:normal 11px Tahoma !
important}.popupHelpTitle{padding-bottom:5px;font-weight:bold;color:black}.nostyle{border:0 solid red !important}.nostyleimg{border:0 solid red !important}.CommandItem{background-color:Transparent;backg
round-image:none}.Grid{border:1px solid #7c7c94;background-color:#fff;cursor:pointer}.HeadingRow{background-color:#e2e2e2}.HeadingCell{background-color:#e2e2e2;border:1px solid #fff;border-right-color:#
b5b5b5;border-bottom-color:#b5b5b5;padding:3px}.HeadingCellText{font-family:verdana;font-size:10px;font-weight:bold;text-align:left}.DataRow{background-color:#fff}.DataCell{cursor:default;padding:3px;bo
rder-right:1px solid #eae9e1;border-bottom:1px solid #eae9e1;font-family:verdana;font-size:10px}.EditDataCell{padding:0 !important;background-color:#e2e2e2;border-width:0 !important}.EditDataField{paddi
ng:0;padding-left:1px;font-family:verdana;font-size:10px;height:20px;width:98% !important}.DataRow td.FirstDataCell{padding-left:3px}.SelectedRow{background-color:#ffeec2}.SelectedRow td.DataCell{cursor
:default;padding:2px;padding-left:3px;padding-bottom:3px;font-family:verdana;font-size:10px;border-bottom:1px solid #4b4b6f;border-top:1px solid #4b4b6f;border-right:0}.SelectorCell{background-color:#e2
e2e2;border:1px solid #fff;border-right-color:#b5b5b5;border-bottom-color:#b5b5b5}.GridFooter{cursor:default;padding:5px}.GridFooter a{color:Black;font-weight:bold;vertical-align:bottom} [...]
I also tried two online utilities: CSS Minifier and CSS Compressor.  The former can be used from the command line or as a web service by  doing a POST request. The latter doesn't offer that option but includes  extra optimizations, such as changing "0px" to "0," or "#FFFFFF" to  "#FFF," and even "#808080" to "gray" (but "black" to "#000"!) so it goes  after every possible byte to be reduced.
 For HTML code, htmlcompressor can minify HTML and XML source, and is available as a command-line Java  jar file for local usage. It has a large number of available options;  type java -jar htmlcompressor-1.5.3.jar --help to check them out. If you are undecided as to which options use, try the -a option, which produces a nice analysis that can help indicate which  command-line options you should use. I tested it with the OpenLogic HTML  file I used in my deflate tests by using the command java -jar htmlcompressor-1.5.3.jar wazi.html -a. I got the following report:
================================================================================
         Setting          | Incremental Gain |    Total Gain    |  Page Size   |
================================================================================
Compression disabled      |         0 (0.0%) |         0 (0.0%) |       75,462 |
All settings disabled     |        79 (0.1%) |        79 (0.1%) |       75,383 |
Comments removed          |     2,042 (2.7%) |     2,121 (2.8%) |       73,341 |
Multiple spaces removed   |     2,492 (3.4%) |     4,613 (6.1%) |       70,849 |
No spaces between tags    |       457 (0.6%) |     5,070 (6.7%) |       70,392 |
No surround spaces (min)  |         0 (0.0%) |     5,070 (6.7%) |       70,392 |
No surround spaces (max)  |         4 (0.0%) |     5,074 (6.7%) |       70,388 |
No surround spaces (all)  |       147 (0.2%) |     5,221 (6.9%) |       70,241 |
Quotes removed from tags  |     1,101 (1.6%) |     6,322 (8.4%) |       69,140 |
 attr. removed      |        95 (0.1%) |     6,417 (8.5%) |       69,045 |
Given this information, you can decide on the actual parameters to  use when compressing the HTML file. A nice touch is that htmlcompressor  can work with YUI Compressor or Closure, and then compress whatever  JavaScript is present in your HTML, for extra savings.
I also tried out Compress HTML and HTML Compressor, two online tools. These are meant to be used online, but the latter project also offers a way to install its code as an inhouse private service; for security reasons, that seems more interesting. The code it produced is certainly more compact:








 [...]
The compressed HTML code is about 10% shorter.
 Note that with all these tools, if your site's HTML code is generated  by a script, a compressor won't be able to compress it effectively.
In conclusion
As you can see, you can take advantage of several ways to reduce file  sizes and in effect speed up your web server. The sum of all  compression functions – server, JavaScript, CSS, and HTML – produces  smaller data transmissions and faster response times. Apply them, and  your users will thank you for it!
0>

Installation

C:\MinGW   /mingw

Compiling a C program

#include 

int main()
{
    std::cout << "Hello, world!\n";
}

g++ hellow.cpp -o hellow

Development environment for native Windows programs

#include 

int main()
{
        int nResult=MessageBox(NULL,
"Hello World",
"Message Box",
                        MB_ICONERROR|MB_OK);
        return 0;
}

Compiling open source programs

cd rhash-1.3.1
make

Conclusion

Get started with open source online

Codecademy

View the complete collection of Beginners in Open Source articles

Code School

Code.org

Scratch

Scratch is a programming language and an online community where children can program and share interactive media such as stories, games, and animation with people from all over the world. As children create with Scratch, they learn to think creatively, work collaboratively, and reason systematically.

Get started with open source offline

Local User Groups

Hackerspaces and makerspaces

Coderdojos

CoderDojo: The open source, volunteer led, global movement of free coding clubs for young people.

Online versus offline

• Age 6-8 and up: Code.org beginner tutorials, Scratch, Coderdojos
• Middle school: Javascript and Python, hackerspace, user groups
• High school: Apps for iOS, hackerspace, user groups

Why Spoof a MAC Address?

How to Spoof a MAC Address Temporarily

Method One: iproute2

Method Two: macchanger

Current MAC:   56:95:ac:ee:6e:77 (unknown)
Permanent MAC: 00:0c:29:97:68:02 (Vmware, Inc.)

How to Spoof a MAC Address Permanently

On Fedora, CentOS or RHEL:

DEVICE=eth0
MACADDR=00:00:00:00:00:01

On Debian, Ubuntu or Linux Mint: