Git: check if something to pull

git remote -v update

PostgreSQL: see number of connections

select sum(numbackends) from pg_stat_database;

Windows: change desktop icon size

1. Using the left click of the mouse, click on an empty area in the desktop. This step is to make sure that there is no application selected/clicked on. 
2. Using your keyboard, press and keep holding the CTRL button, then using your mouse wheel, roll it upward to make the icons size larger, or downward to set the icon size smaller

Virtualbox centos: Device eth0 does not seem to be present

If, when copying a VM from one computer to another one, you face this error:

service network restart
...
Bringing up interface eth0: Device eth0 does not seem to be present, delaying initialization.

Then ensure first that /etc/sysconfig/network-scripts/ifcfg-eth0 has the same MAC address as in Virtualbox network settings, plus

rm /etc/udev/rules.d/70-persistent-net.rules

and reboot

Cisco AnyConnect - Adding Multiple VPN Devices to the Client

See http://www.petenetlive.com/KB/Article/0001011.htm

• Windows: vi C:\ProgramData\Cisco\Cisco AnyConnect Secure Mobility Client\profile\Profile.xml
• MacOS: vi /opt/cisco/anyconnect/profile/Profile.xml

 
  false
  true
  false
  All
  false
  Native
  true
  12
  false
  true
  true
  true
  true
   DisconnectOnSuspend
  
  true
  Automatic
  SingleLocalLogon
  LocalUsersOnly
  false
  Disable
   
  
  false
  false
   20
   4
  
  false
  
 
 
  
   My entry #1
   my_entry1.com
  
  
   My entry #2
   my_entry2.com
  
 

PostgreSQL: epoch to date

select to_timestamp(1446631729) at time zone 'UTC';

Git: show files not yet pushed

git diff --numstat origin/master

SOAP: Error fetching http headers

http://php.blogaboutwhatever.com/2011/11/error-fetching-http-headers/

Git: cancel staged file update

With git log check which commit is one prior the update. Then you can reset it using:

git reset  filename
git checkout filename

Git: cancel merge

With git log check which commit is one prior the merge. Then you can reset it using:

git reset --hard commit_sha

PostgreSQL: upsert

With a lock: http://www.the-art-of-web.com/sql/upsert/
Discussion: http://www.depesz.com/2012/06/10/why-is-upsert-so-complicated/
PostgreSQL doc.: http://www.postgresql.org/docs/current/static/plpgsql-control-structures.html#PLPGSQL-UPSERT-EXAMPLE

OSX: use Clover Configurator

First mount EFI partition:
Identify EFI device

diskutil list

Then mount device, e.g.

mkdir /Volumes/EFI
sudo mount_msdos /dev/disk0s1 /Volumes/EFI

Then select /Volumes/EFI/EFI/CLOVER/config.plist in Clover configurator

OSX: Errors in audio_cloverALC-110_v1.0h

See https://github.com/toleda/audio_CloverALC/issues/43

OSX: Clover install on El Capitan

How To Install OS X Yosemite Using Clover

PostgreSQL: compile pgloader

Compile SBCL with core compression support:

git clone git://git.code.sf.net/p/sbcl/sbcl
cd sbcl
./make.sh --with-sb-core-compression --with-sb-thread
sudo ./install.sh

Compile pgloader:

git clone https://github.com/dimitri/pgloader.git
cd pgloader
make
sudo cp ./build/bin/pgloader /usr/bin

PostgreSQL: generate create table SQL

pg_dump -t 'my_schema.my_table' --schema-only

PostgreSQL: interval to number of days

select extract(epoch from my_interval)/86400;

Postgresql: import export of data

Export

copy (select * from shared_db.dt_process where process_name = 'AM_PARTITION') to '/tmp/shared_db__dt_process.csv' delimiter ',' csv header;

Import

copy shared_db.dt_process from '/tmp/shared_db__dt_process.csv';

CentOS: install Oracle JDK

• Download JDK from download.oracle.com

• cd /usr/local/share
  tar xvfz /media/host/jdk-8u60-linux-x64.tar.gz
  ln -s jdk1.8.0_60 jdk

• alternatives --install /usr/bin/java java /usr/local/share/jdk/bin/java 1
  alternatives --install /usr/bin/javac javac /usr/local/share/jdk/bin/javac 1
  alternatives --install /usr/bin/jar jar /usr/local/share/jdk/bin/jar 1

OSX: pipe

shift + Right Alt + l

CentOS 6 VM: french Macbook keyboard under X11

setxkbmap -layout fr -model macintosh

QNAP: add dnsomatic cronjob

Source: http://forum.qnap.com/viewtopic.php?t=12970

vi /share/CACHEDEV1_DATA/homes/dnsomatic/dnsomatic.sh

#!/bin/sh
HOSTNAME="all.dnsomatic.com"
USER="my_dnsomatic_user"
PASS="my_dnsomatic_password"
TMPFILE="/tmp/dnsomatic.oldip"
DATENOW=$(date)
 
IP=$(/sbin/curl -s http://myip.dnsomatic.com)
if [ -r "/tmp/dnsomatic.oldip" ]; then
 OLDIP=`cat /tmp/dnsomatic.oldip`
 if [ "$OLDIP" = "$IP" ]; then
  echo "IPs match; no update"
  exit 0
 else
  RETURN=$(/sbin/curl -s -m 60 -k -u ${USER}:${PASS} https://updates.dnsomatic.com/nic/update?hostname=${HOSTNAME}&myip=$IP&wildcard=NOCHG&mx=NOCHG&backmx=NOCHG)
  echo "Return message of DNS-O-Matic : " $RETURN
  echo $RETURN | grep "good" > /dev/null 2>&1
  if [ "$?" -eq "0" ]; then
   echo $IP > /tmp/dnsomatic.oldip
  else
   echo "" > /tmp/dnsomatic.oldip
  fi
 fi
else
 touch /tmp/dnsomatic.oldip
fi

Then update crontab to run it once an hour:

 vi /etc/config/crontab

0 */1 * * * /share/CACHEDEV1_DATA/homes/dnsomatic/dnsomatic.sh >/tmp/dnsomatic.log 2>&1

crontab /etc/config/crontab
/etc/init.d/crond.sh restart

PostgreSQL: copy table

select * into archive.radius_cdr_pdp_p2015_07_09 from ods_db.radiucdr_pdp_p2015_07_09;

PostgreSQL: get function source code

select pg_get_functiondef(pg_proc.oid) from pg_proc, pg_namespace  where proname = 'add_cdr_req' and pg_namespace.oid = pg_proc.pronamespace and pg_namespace.nspname = 'crm_db';

Displaying current path in the window title with byobu on centos 6

The problem with CentOS 6, is that the tmux version that comes from the standard repo. is v1.6, and we need at least 1.8 to achieve the result.
So install tmux from the latest sources like explained here:

# download latest libevent2 and tmux sources, and extract them somewhere
# (thx bluejedi for tip on latest tmux URL)
#
# at the time of writing:
# https://github.com/downloads/libevent/libevent/libevent-2.0.21-stable.tar.gz
# http://sourceforge.net/projects/tmux/files/latest/download?source=files
# 
 
# install deps
yum install gcc kernel-devel make ncurses-devel
 
# cd to libevent2 src
./configure --prefix=/usr/local
make && make install
 
# cd to tmux src
LDFLAGS="-L/usr/local/lib -Wl,-rpath=/usr/local/lib" ./configure --prefix=/usr/local
make && make install
 
# you're good to go, for a sample ~/.tmux.conf check out
# https://github.com/sturadnidge/misc/blob/master/.tmux.conf

NB: Kill old tmux sessions before running byobu again.
And then use the following setting in your $HOME/.byobu/.tmux.conf

set -g status-left '#{pane_current_path} '

Linux: Running processes with associated open port

netstat -tulpn

byobu: Show pwd in prompt

Enable prompt

byobu-enable-prompt

Disable prompt

byobu-disable-prompt

mod_perl: How to send a custom content type along with custom_response

By default, mod_perl Apache2::Response::custom_response will use the following content-type: text/html; charset=iso-8859-1.
But, what if we want to use e.g. application/x-www-form-urlencoded; charset=utf-8 instead?

Main handler:

sub handler {
    my ($i_request_rec) = @_;

    @{$i_request_rec->pnotes}{'err_txt', 'err_content_type'} = ('appid=45465&status=-42', 'application/x-www-form-urlencoded; charset=utf-8');
    $i_request_rec->custom_response(Apache2::Const::SERVER_ERROR, '/error_vas/');
    return Apache2::Const::SERVER_ERROR;
}

Apache conf.:

<Location /error_vas/>
        SetHandler perl-script
        PerlResponseHandler Toto::ErrorVas
</Location>

ErrorVas.pm:

package Toto::ErrorVas;

use strict;
use warnings;
use Apache2::Const -compile => qw(:common :log);

sub handler {
    my ($i_request_rec) = @_;

    return Apache2::Const::NOT_FOUND unless $i_request_rec->prev;

    $i_request_rec->content_type($i_request_rec->prev->pnotes->{err_content_type});
    $i_request_rec->print($i_request_rec->prev->pnotes->{err_txt});

    return Apache2::Const::OK;
}

source: http://foertsch.name/ModPerl-Tricks/custom-content_type-with-custom_response.shtml

perl: setting multiple hash values at once

perl -MData::Dumper -e '@{$h}{qw/toto tata/} = (34, 56); print Dumper $h;'              
$VAR1 = {
          'tata' => 56,
          'toto' => 34
        };

perl: posting to multihomed hostname

What if you want to post to a hostname resolving to multiple IP addresses?

    local @LWP::Protocol::http::EXTRA_SOCK_OPTS = (
                                                   PeerAddr   => $my_hostname,
                                                   MultiHomed => 1,
                                                  );
    my $ua = LWP::UserAgent->new;
    my $response = $ua->post("https://$my_hostname/action",
                             Content_Type => 'application/x-www-form-urlencoded; charset=utf-8',
                             Content      => {
                                              param1 => 'value1',
                                              param2 => 'value2',
                                             });

php/oci-extension: missing leading zero

Reading numbers from Oracle in PHP results in missing leading 0s if -1 < value < 1.
The reason for this behavior is because Oracle OCI omits 0s in results and PHP converts all results from OCI to strings without performing any casting depending on column datatype.

A simple workaroud consists in converting to float:

$a = '.63';
echo (float) $a;

source: http://stackoverflow.com/questions/4284571/php-oci-oracle-and-default-number-format

Oracle alternative:

REGEXP_REPLACE(TO_CHAR(x), '^\.', '0.')

or if we handle negative numbers

REGEXP_REPLACE(TO_CHAR(x), '(-?)^\.', '\10.')

perl: print module version

perl -MLWP::UserAgent -e 'print $LWP::UserAgent::VERSION'

HTML: POST array not showing unchecked checkbox

<td>
  <input type="checkbox" name="cb[]"/>
  <input type="checkbox" name="cb[]"/>
</td>

• Solution 1) Explicit index + hidden trick

<td>
  <input type="hidden" name="cb[0]" value=""/>
  <input type="checkbox" name="cb[0]"/>
  <input type="hidden" name="cb[1]" value=""/>
  <input type="checkbox" name="cb[1]"/>
</td>

• Solution 2) Explicit index + fill in the blanks (e.g. with PHP)

<td>
  <input type="checkbox" name="cb[0]"/>
  <input type="checkbox" name="cb[1]"/>
</td>

$post_array = $_POST['cb'];
$defaults = array_fill(0, 2, '0');
$post_array = $post_array + $defaults;

byobu: terminate tmux session

tmux kill-session

Byobu keybindings

https://github.com/dustinkirkland/byobu/blob/master/usr/share/doc/byobu/help.tmux.txt

PostgreSQL: perl like join

db=# select array_to_string(array['a', 'b', 'c'], '-');                                                                     
 array_to_string 
-----------------
 a-b-c
(1 row)

PostgreSQL: date to epoch

select extract(epoch from localtimestamp(0));

PostgreSQL: cursor example

create or replace function test_cursor() returns void as
$$
declare
    _my_cursor(p_co_id text) for
        select * from crm_db.ht_co_addon where co_id = p_co_id;
    _idx int := 0;
    _row record;
begin
    -- Example 1
    for _row in _my_cursor('000000000666') loop
        _row.co_addon_id := _idx;
        _idx := _idx + 1;
    end loop;

    -- Example 2
    open _my_cursor('000000000666')
    loop
        fetch _my_cursor into _row
        exit when not found
        raise notice 'co_addon_id=%', _row.co_addon_id
    end loop
    close _my_cursor
end;
$$ language plpgsql security definer;

PostgreSQL: hstore or a perl like hash table

create or replace function test_hstore() returns void as
$$
declare
    _my_cursor(p_co_id text) for
        select * from crm_db.ht_co_addon where co_id = p_co_id;
    _row record;
    _addon_id2co_addon_id_h hstore;
    _sms_ao text := 'SMS_AO';
begin
    for _row in _my_cursor('000000000666') loop
        if _addon_id2co_addon_id_h is null then
            _addon_id2co_addon_id_h := (_row.addon_id||'=>'||_row.co_addon_id)::hstore;
        else
            _addon_id2co_addon_id_h := _addon_id2co_addon_id_h || (_row.addon_id||'=>'||_row.co_addon_id)::hstore;
        end if;
    end loop;

    raise notice 'SMS_AO: %', _addon_id2co_addon_id_h->_sms_ao;

    for _row in select * from each(_addon_id2co_addon_id_h) loop
        raise notice 'h: %=>%', _row.key, _row.value;
    end loop;
end;
$$ language plpgsql security definer;

Linux: remove files older than x days

E.g. Remove files older than 90 days

find . -mtime +90 -exec rm {} \;

Git merge master into feature branch

Source: http://stackoverflow.com/questions/16955980/git-merge-master-into-feature-branch

You should be able to rebase your branch on master:

git checkout feature1
git rebase master

Manage all conflicts that arise. When you get to the commits with the bugfixes (already in master), git will say that there were no changes and that maybe they were already applied. You then continue the rebase (while skipping the commits already in master) with

git rebase --skip

If you perform a git log on your feature branch, you'll see the bugfix commit appear only once, and in the master portion.

git: change remote repository

Context: I have used bitbucket as a remote git repository so far, and now I want to switch to a corporate git server.

Following the instructions detailled here: http://www.smashingmagazine.com/2014/05/19/moving-git-repository-new-server/
Here are the steps eventually run:

git fetch origin
git remote add new-origin ssh://john.smith@192.168.2.3/volume1/git-server/is.git
git pull new-origin master
git push --all new-origin
git push --tags new-origin
git remote rm origin
git remote rename new-origin origin

Git: Sync remote repository w/ local

From http://stackoverflow.com/questions/6373277/git-sync-local-repo-with-remote-one

cd $HOME/src
git pull -p

NB: git pull runs git fetch with the given parameters and calls git merge to merge the retrieved branch heads into the current branch - git-scm.com/docs/git-pull

-p, --prune After fetching, remove any remote-tracking branches which no longer exist on the remote

Git workflows

https://www.atlassian.com/git/tutorials/comparing-workflows

SSH with keep alive option

ssh -o "ServerAliveInterval 600" yapit

Disable Strict SSH Checking on Source Peer

By appending the following to your ~/.ssh/config file you can disable SSH prompts which ask to add new hosts to the “known hosts file.” Note that the ${DESTPEERHOST} should be the name of the host machine running the destination peer:

Host ${DESTPEERHOST}
CheckHostIP no
StrictHostKeyChecking no
BatchMode yes

SSH to tondu as omnitest without password

• As gallinar, in .ssh/config, comment “Batchmode yes” so as to temporarily get a password question when sshing:

 #BatchMode yes

• As gallinar, in .ssh/config, add the following lines in order to log to tondu as omnitest:

 Host tndu
 HostName tondu
 User omnitest

• As gallinar, if not already done, generate a public key:

 ssh-keygen -t rsa

• As gallinar, copy the public key to the target:

 scp ~/.ssh/id_rsa.pub tondu:/tmp

• As omnitest, on tondu:

 cat /tmp/id_rsa.pub >> ~/.ssh/authorized_keys

• As gallinar, in .ssh/config, uncomment “Batchmode yes”, and remove /tmp/id_rsa.pub on tondu.

Configured ssh on host for no password but still asked

Check $HOME/.ssh and $HOME rights. If writeable for group or world, a password will be asked.

> chmod 700 $HOME/.ssh 
> chmod 600 $HOME/.ssh/authorized_keys

Virtualbox: Shrinking VM Disk Images

Source: http://snippets.khromov.se/shrinking-a-virtualbox-linux-image-with-zerofree/

• Download the SystemRescueCd Live Image
Mount it as a CD on your virtual machine and boot into the live distro
• Find all available partition and LVM (volume groups) with:

fdisk -l

• After we find our partition run zerofree to zero out the free space. In our example we will run it on the LVM root partition

zerofree -v /dev/mapper/vg_rheldev-lv_root

• Finally, boot down your virtual machine, and run VBoxManage on the host to resize the .vdi file

C:\>"c:\Program Files\Oracle\VirtualBox\VBoxManage.exe" modifyhd "c:
\Users\jerome\VirtualBox VMs\Monster\Mobiquithings.vdi" --compact

With this method, my VM shrunk from 200 GiB to 26 GiB

NB: The other method mentioned on the net replacing zerofree with dd like in

dd -if /dev/zero -of /bigemptyfile -bs 4096; rm /bigemptyfile

was not satisfactory for me.

Radius: run time variables

http://wiki.freeradius.org/config/Run%20time%20variables

xemacs: Unable to load any usable fontset

If running XEmacs causes these warnings about fonts:

[jerome@mathusalem] > xemacs
Warning: Missing charsets in String to FontSet conversion
Warning: Cannot convert string "-*-helvetica-bold-r-*-*-*-120-*-*-*-*-iso10646-1,                               -*-helvetica-bold-r-*-*-
*-120-*-*-*-*-iso8859-*,                                *" to type FontSet
Warning: Missing charsets in String to FontSet conversion
Warning: Unable to load any usable fontset
Warning: Missing charsets in String to FontSet conversion
Warning: Unable to load any usable fontset

Then, try running it this way:

[jerome@mathusalem] > LANG=C xemacs

Windows Virtualbox: increase CentOS 6 VDI size

1. Create a new VDI disk under Controller: SATA, sized appropriately





2. Clone existing VDI into new one

C:\Program Files\Oracle\VirtualBox> VBoxManage.exe clonehd "c:\Users\jerome\VirtualBox VMs\Mathusalem\Mathusalem.vdi" --existing "c:\Users\jerome\VirtualBox VMs\Mathusalem\Mathusalem 2.vdi"

0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VDI'. UUID: 48da07eb-3395-4fad-95e3-c0615b185da2

3. Remove legacy VDI



4. Download GParted ISO from GParted Live CD
5. Mount GParted ISO under Controller: IDE



6. Start the VM, which will boot on the GParted live CD
7. Extend the existing LVM2 partition (/dev/sda2) with the new unallocated space
8. Stop the VM, detach the GParted ISO, and reboot the VM
9. Extend the logical volume into the resized partition
By default, CentOS uses LVM (Logical Volume Manager), which requires an extra step.
Identify the name of the logical volume via df:

df -h



Then force the LVM volume to take 100% of the available space on the partition:

lvextend -l +100%FREE /dev/mapper/vg_mathusalem-lv_root

10. Resize file system

resize2fs /dev/mapper/vg_mathusalem-lv_root


After this step, we are now good to go.

Oracle: split / join

See http://stackoverflow.com/questions/381231/hidden-features-in-oracle

SQL> declare
  2    v_array apex_application_global.vc_arr2;
  3    v_string varchar2(2000);
  4  begin
  5  
  6    -- Convert delimited string to array
  7    v_array := apex_util.string_to_table('alpha,beta,gamma,delta', ',');
  8    for i in 1..v_array.count
  9    loop
 10      dbms_output.put_line(v_array(i));
 11    end loop;
 12  
 13    -- Convert array to delimited string
 14    v_string := apex_util.table_to_string(v_array,'|');
 15    dbms_output.put_line(v_string);
 16  end;
 17  /
alpha
beta
gamma
delta
alpha|beta|gamma|delta

Oracle: dense_rank explanation

RANK, DENSE_RANK, FIRST and LAST Analytic Functions

Oracle: return a row even if select returns no rows

SELECT nvl(data_name, 'nothing') FROM (  
    SELECT data_name
    FROM data_table
    WHERE data_table.type = v_t_id

    UNION ALL

    SELECT NULL AS data_name
    FROM dual
  ) WHERE data_name is not null or ROWNUM = 1;

perl: one-liner with single quotes in

cat /media/host/export_PYF_NCL.csv | perl -e 'while(<>){print "'"'"'$1'"',"'" if /^(\d+);/}'