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Error Checking for Functions in Siebel eScript

Some functions return a special value if they fail to do what they are supposed to do. For example, the Clib.fopen() method opens or creates a file for a script to read from or write to. If the computer is unable to open a file, the Clib.fopen() method returns null.

If you try to read from or write to a file that was not properly opened, you receive errors. To prevent these errors, make sure that Clib.fopen() does not return null when it tries to open a file. Instead of calling Clib.fopen() as follows:

var fp = Clib.fopen("myfile.txt", "r");

check to make sure that null is not returned:

var fp = Clib.fopen("myfile.txt", "r");

if (null == fp)
{
   TheApplication().RaiseErrorText("Error with fopen as returned null" +
   "In the following object" + this.Name() + " " e.toString() + e.errText());
}

You may abort a script in such a case, but you then know why the script failed. Read The Clib Object.