execute(s)                   execute string
execute(s,se)                execute string
execute(s,se,rf)             execute string

    Execute string s as an QTAwk statement or expression.  The parameter se
    determines whether s  is executed as  a string or  expression.  For  se
    FALSE (default  value for  first form),  s is  assumed to  be an  QTAwk
    statement  and  executed  as  such.    For  se TRUE, s is assumed to an
    expression and executed as such. the rf parameter determines the  error
    recovery  of  QTAwk.    For  rf  ==  FALSE (default value for first two
    forms), any  error in  parsing or  executing s,  halts QTAwk execution.
    For rf == TRUE, QTAwk halts parsing or execution of s only.

    If the current input record is:

    new_str = "The new value of any variable";

    then:

    print execute($0);

    or

    print execute($0,0);

    will both set the variable 'new_str' to the string value:

                        "The new value of any variable"

    and output the value one, 1.

    print execute($0,1);

    will also set the variable 'new_str', but will output:

             "The new value of any variable"

    The input record:

    { w_page = 85; l_page = 88; top_m = 5; bottom_m = 5; }

    will set the four variables to the values:

    w_page = 85;
    l_page = 88;
    top_m = 5;
    bottom_m = 5;

    when the following is executed:

    execute($0);

    or

    execute($0,0);

execute(a)                   execute array
execute(a,se)                execute array
execute(a,se,rf)             execute array

    The last example above could also  be executed using the array form  of
    the execute  statement.   The se  and rf  parameters are  as for string
    execution above.  With the array:

    set_val[1] = "{";
    set_val[2] = "w_page = 85;";
    set_val[3] = "l_page = 88;";
    set_val[4] = "top_m = 5;";
    set_val[5] = "bottom_m = 5;";
    set_val[6] = "}";

    Then:

    execute(set_val);

    or

    execute(set_val,0);

    will execute the array as a  single statement and set the variables  as
    indicated.  The array could have been executed as an expression:

    set_val[1] = "w_page = 85,";
    set_val[2] = "l_page = 88,";
    set_val[3] = "top_m = 5,";
    set_val[4] = "bottom_m = 5;";

    then

    execute(set_val,1);

    will set the variables as indicated and return a value of five, 5.