Using arrays in bash using strings to bash built-in true Post: 302616095

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Top Forums Shell Programming and Scripting Using arrays in bash using strings to bash built-in true Post 302616095 by kristinu on Friday 30th of March 2012 07:59:28 PM

03-30-2012

Registered User

Yes, I am trying to get the scripts working and then improve them as I get to know more. I need to get some results quick but need some scripts to do what I need.

---------- Post updated at 06:59 PM ---------- Previous update was at 12:11 PM ----------

Quote:

Originally Posted by Corona688

Like we've been telling you all along, shell does not have boolean. Even program return codes aren't boolean.

They return zero for success, and nonzero for anything else. There's lots of different possible return codes -- often 255 -- so that they can return different codes for different errors. true returns 0, and false returns 1, so that it can be used properly in the shell.

Code:

true && echo "this will print"
false && echo "but this won't"
true || echo "neither will this"
false || echo "but this will"

You could consider true and false shortcuts to turn the strings true and false into usable return codes, I suppose.

This worked

Code:

hello=true
val=1
echo "if $hello || [ $val -eq 3 ]; then"
if $hello || [ $val -eq 3 ]; then
  echo "HELLO"
fi

kristinu

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apc_inc

APC_INC(3)								 1								APC_INC(3)

apc_inc - Increase a stored number

SYNOPSIS

       int apc_inc (string  $key, [int	$step = 1], [bool  &$success])

DESCRIPTION

	Increases a stored number.

PARAMETERS

	      o $key
		- The key of the value being increased.

	      o $step
		- The step, or value to increase.

	      o $success
		- Optionally pass the success or fail boolean value to this referenced variable.

RETURN VALUES

	Returns the current value of $key's value on success, or FALSE on failure

EXAMPLES

       Example #1

	      apc_inc(3) example

	      <?php
	      echo "Let's do something with success", PHP_EOL;

	      apc_store('anumber', 42);

	      echo apc_fetch('anumber'), PHP_EOL;

	      echo apc_inc('anumber'), PHP_EOL;
	      echo apc_inc('anumber', 10), PHP_EOL;
	      echo apc_inc('anumber', 10, $success), PHP_EOL;

	      var_dump($success);

	      echo "Now, let's fail", PHP_EOL, PHP_EOL;

	      apc_store('astring', 'foo');

	      $ret = apc_inc('astring', 1, $fail);

	      var_dump($ret);
	      var_dump($fail);
	      ?>

	      The above example will output something similar to:

	      42
	      43
	      53
	      63
	      bool(true)
	      Now, let's fail

	      bool(false)
	      bool(false)

SEE ALSO 
apc_dec(3).
PHP Documentation Group 														APC_INC(3)