CUSTOM.pll

CUSTOM.pll is a Library file and it is a package to modify the existing forms without touching  the fmb's and we are having only one CUSTOM.pll

Location of the CUSTOM.pll:-
 By default all .pll and .plx files are available in AU_TOP/11.5.0/resource folder.

Advantages of CUSTOM.pll:-

• By using CUSTOM.pll we can code ZOOM functionality calling a form to another form.
• We can change the existing form behavior by writing custom application logic.
• We can modify LOV's
• We can change the validations for fields like items, buttons, blocks, drop list items ..etc
• We can create new special menu's
• CUSTOM.pll does not effect by applying the patches.

Disadvantages:-

•  Not possible to modify by more than one user at a time because there is only one CUSTOM.pll file available.  
• Not possible to call all the triggers in CUSTOM.pll(Like item level validations)
• CUSTOM.pll have size limitation issue. We can't write package code more than 32kb.
• Maintaining code modularity is difficult as the data is not stored in tables like form personalization.