Question for calling oracle function from perl

Shell Programming and Scripting
1

Dear Sir/Madam,

I use the following way to call the oracle stored procedure in a perl script, but I do not know how to call a oracle function by the following way ?

 # ARGV[0] is the oracle stored procedure name with parameters

  $str = "sqlplus -s <<-eof \n" .
            "$db_login \n" .
            "WHENEVER SQLERROR EXIT FAILURE; \n" .
            "EXEC @ARGV[0]; \n".
            "exit; \n".
            "EOF\n";

$return_code = system($str);

printf STDERR "$str\n";

Thanks
ili