How to take screenshot in mac

use command+shift+3 to take a screen shot of your entire screen.(or)
use command+shift+4 ,mac osx turns cursor into crosshairs,
press spacebar,you will get a little camera,
use that to take screenshot

Running a c pgm in unix

step 1:create a c file in your directory.


step 2:compile it using cc -o programname sourcefile.c.This makes a file named programname in the same directory.(or) compile it using gcc sourcefile.c.This makes a file named a.out in the same directory.


step 3:Run it using ./programname (or) ./a.out.

How to separate a string using explode in php

ex:
$st= explode('-', date('Y-m-d',strtotime('2010-01-01')));
result:
Array
(
[0] => 2010
[1] => 01
[2] => 01
)

How to reset a single file in git

If you have changed a file in your working copy,but not commited yet,then you can restore that file to the version in the HEAD revision using,
git checkout HEAD hello.js

How to sort an two-dimensional array with respect to an element

$item_arr=Array
(
[0] => Array
(
[resourceid] => 854
[refno] => 268475
[fax] => +61 2 6198 3333
[phone] => +61 2 6198 3300
)

[1] => Array
(
[resourceid] => 750
[refno] => 268476
[fax] => +61 8 8233 5858
[phone] => +61 8 8233 5888
)

[2] => Array
(
[resourceid] => 675
[refno] => 268477
[fax] => +91 40 4033 9999
[phone] => +91 40 4033 9900
)

[3] => Array
(
[resourceid] => 522
[refno] => 268478
[fax] => +86 10 8520 0110
[phone] => +86 10 8520 0000
)

[4] => Array
(
[resourceid] => 647
[refno] => 268479
[fax] => +86 21 6103 7070
[phone] => +86 21 6103 7000
)

)
to sort above array with respect to refno,

function sorter($a, $b) { return $a["refno"] > $b["refno"]; }
usort($item_arr,"sorter");