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Full Discussion: How to correctly use an echo inside an echo?
Top Forums UNIX for Dummies Questions & Answers How to correctly use an echo inside an echo? Post 302354802 by raja_kolluru on Saturday 19th of September 2009 11:40:18 PM
Old 09-20-2009
Quote:
Originally Posted by mokachoka
Bit of a weird one i suppose, i want to use an echo inside an echo... For example...

i have a script that i want to use to take users input and create another script. Inside this script it creates it also needs to use echos...

echo "echo "hello"" >$file
echo "echo "goodbye"" >$file

Why is this not correct?

Thanks.
A few observations here:
1. As suggested earlier, either "escape" the double quotes surrounding "hello" or use single quote i.e. use
Code:
 echo "echo \"Hello\" "
or echo "echo 'hello' "

2. By doing >$file two times the second echo (i.e. good bye) will over write $file. Instead use
Code:
 echo "echo 'goodbye'" >> $file

to append the contents of the echo into the file.
3. It is a best practice to refrain from creating elaborate scripts using the echo command. Instead use shell "here documents"
Code:
cat <<! > $file
echo "Hello" 
echo "Good bye" 
!

is certainly a lot cleaner.
 

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LEARN ABOUT PHP

boolval

BOOLVAL(3)								 1								BOOLVAL(3)

boolval - Get the boolean value of a variable

SYNOPSIS

       boolean boolval (mixed  $var)

DESCRIPTION

	Returns the boolean value of $var.

PARAMETERS

	      o $var
		- The scalar value being converted to a boolean.

RETURN VALUES

	The boolean value of $var.

EXAMPLES

       Example #1

	      boolval(3) examples

	      <?php
	      echo '0:	      '.(boolval(0) ? 'true' : 'false')."
";
	      echo '42:       '.(boolval(42) ? 'true' : 'false')."
";
	      echo '0.0:      '.(boolval(0.0) ? 'true' : 'false')."
";
	      echo '4.2:      '.(boolval(4.2) ? 'true' : 'false')."
";
	      echo '"":       '.(boolval("") ? 'true' : 'false')."
";
	      echo '"string": '.(boolval("string") ? 'true' : 'false')."
";
	      echo '"0":      '.(boolval("0") ? 'true' : 'false')."
";
	      echo '"1":      '.(boolval("1") ? 'true' : 'false')."
";
	      echo '[1, 2]:   '.(boolval([1, 2]) ? 'true' : 'false')."
";
	      echo '[]:       '.(boolval([]) ? 'true' : 'false')."
";
	      echo 'stdClass: '.(boolval(new stdClass) ? 'true' : 'false')."
";
	      ?>

	      The above example will output:

	      0:	false
	      42:	true
	      0.0:	false
	      4.2:	true
	      "":	false
	      "string": true
	      "0":	false
	      "1":	true
	      [1, 2]:	true
	      []:	false
	      stdClass: true

SEE ALSO

       floatval(3), intval(3), strval(3), settype(3), is_bool(3), Type juggling.

PHP Documentation Group 														BOOLVAL(3)
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