Hi
I have a variable which is a path ie:
UBERROR=/cobwrk/mchr/prodsup/ub/wrk/../error
is there anyway I can get the output of an echo to read:
#echo $UBERROR
/cobwrk/mchr/prodsup/ub/error
instead of
#echo $UBERROR
/cobwrk/mchr/prodsup/ub/wrk/../error
Many thanks! (2 Replies)
I would like to know how to pass a variable inside a variable to a function.
sample code below
--------------
for x in 1 9
do
check_null $C$x ##call function to check if the value is null
if
then
echo "line number:$var_cnt,... (2 Replies)
Hi Gurus
I have a file called /tmp/CMDB which looks like this
serial: 0623AN1208
hostname: server1
model: x4100
assetID: 1234
I am writing a for loop that will go through this file line by line creating a variable of itself. Using the first iteration of the loop (i.e. the first line) as... (6 Replies)
Hi,
I am trying to do the following thing
var='date'
$var
Above command substitutes date for and in turn runs the date command and i am getting the todays date value.
I am trying to do the same thing as following, but facing some problems,
unique_host_pro="sed -e ' /#/d'... (3 Replies)
Hi there, i think im getting myself a little confused and need some help :wall:
I am reading in a bunch of variables to my script from an external file and need to validate that a value has been set for each
so if you can imagine, the user is required to pass in 4 values... (3 Replies)
I am tyring to resolve an environment variable that is part of a string I selected from our database.
Simply put, I want cd to this folder before checking if a file exists.
The variable $in_loc has the value '$PS_HOME/int/VSP' where $PS_HOME is the environment variable.
I am using cd... (6 Replies)
Hi All,
I have below variable,
xyz=\$AI_XFR
Now, if you will run the below command
=> echo $xyz
$AI_XFR
It is returning hardcoded string value.
Whereas in environment, there is value in it. Like below:
=> echo $AI_XFR
/home/aditya/sandbox/xfr/
I need to resolve this... (4 Replies)
My script
----------
for i in `cat n`;do
export k=`echo "CSN: "$i` //combining CSN: and value from n
echo "$k"
awk ''{print "CSN: "$0;}'{_=29}_&&_--' file1|tail -1 >> file2
done
In the above script i cannot able to resolve $k in awk command
file n contains
------------
0000
1111
2222... (2 Replies)
Hi guys,
I have a file "abc.dat" in below format:
FILE_PATH||||$F_PATH
TABLE_LIST||||a|b|c
SYST_NM||||${SRC_SYST}
Now I am trying to read the above file and want to print the value for above dollar variables F_PATH and SRC_SYST. The problem is it's reading the dollar variables as... (5 Replies)
Discussion started by: abcabc1103
5 Replies
LEARN ABOUT PHP
unset
UNSET(3) 1 UNSET(3)unset - Unset a given variableSYNOPSIS
void unset (mixed $var, [mixed $...])
DESCRIPTION unset(3) destroys the specified variables.
The behavior of unset(3) inside of a function can vary depending on what type of variable you are attempting to destroy.
If a globalized variable is unset(3) inside of a function, only the local variable is destroyed. The variable in the calling environment
will retain the same value as before unset(3) was called.
<?php
function destroy_foo()
{
global $foo;
unset($foo);
}
$foo = 'bar';
destroy_foo();
echo $foo;
?>
The above example will output:
bar
To unset(3) a global variable inside of a function, then use the $GLOBALS array to do so:
<?php
function foo()
{
unset($GLOBALS['bar']);
}
$bar = "something";
foo();
?>
If a variable that is PASSED BY REFERENCE is unset(3) inside of a function, only the local variable is destroyed. The variable in the
calling environment will retain the same value as before unset(3) was called.
<?php
function foo(&$bar)
{
unset($bar);
$bar = "blah";
}
$bar = 'something';
echo "$bar
";
foo($bar);
echo "$bar
";
?>
The above example will output:
something
something
If a static variable is unset(3) inside of a function, unset(3) destroys the variable only in the context of the rest of a function. Fol-
lowing calls will restore the previous value of a variable.
<?php
function foo()
{
static $bar;
$bar++;
echo "Before unset: $bar, ";
unset($bar);
$bar = 23;
echo "after unset: $bar
";
}
foo();
foo();
foo();
?>
The above example will output:
Before unset: 1, after unset: 23
Before unset: 2, after unset: 23
Before unset: 3, after unset: 23
PARAMETERS
o $var
- The variable to be unset.
o $...
- Another variable ...
RETURN VALUES
No value is returned.
EXAMPLES
Example #1
unset(3) example
<?php
// destroy a single variable
unset($foo);
// destroy a single element of an array
unset($bar['quux']);
// destroy more than one variable
unset($foo1, $foo2, $foo3);
?>
Example #2
Using (unset) casting
(unset) casting is often confused with the unset(3) function. (unset) casting serves only as a NULL-type cast, for completeness. It
does not alter the variable it's casting.
<?php
$name = 'Felipe';
var_dump((unset) $name);
var_dump($name);
?>
The above example will output:
NULL
string(6) "Felipe"
NOTES
Note
Because this is a language construct and not a function, it cannot be called using variable functions.
Note
It is possible to unset even object properties visible in current context.
Note
It is not possible to unset $this inside an object method since PHP 5.
Note
When using unset(3) on inaccessible object properties, the __unset() overloading method will be called, if declared.
SEE ALSO isset(3), empty(3), __unset(), array_splice(3).
PHP Documentation Group UNSET(3)