The isset() function determines whether a variable has been set. A variable with a blank or zero value returns true, because blank and zero are considered values.
result = isset (string);
string Required. A string that contains a variable name.
|true||Integer. The specified variable has a value.|
|false||Integer. The specified variable does not have a value.|
runhost = "beyondtrust1"; result = isset ("runhost");
In this example, result contains an integer value of 1 (true) because the runhost variable has a value of beyondtrust1.
For more information, please see unset.