The u009e user exit replaces all occurrences of str1 with str2 in str3.
xx = oconv("u":am:str1:am:str2:am: str3, "u9e")
xx=oconv("u":am:"jan":am:"feb":am:"The month is jan","u9e") The value of xx is "The month is feb".
convert statement, s (substitution) processing code