Rexx Pull is not working with clrscrn after Displaying ispf Panel

Question

Currently i am writing a rexx program in which i need to mask password input. I use this code to get my panel displayed:

address ispexec"libdef ispplib dataset id('my.pds')
address ispexec 'display panel(member)'

This works perfectly, and returns the password to a variable, in which i perform various checks on.

After that i continue on in my rexx program. the next function that occurs, is taking in input from the user by using Rexx's 'say' 'pull' method. This is where the weird error occurs.

I have to check user input again, if its invalid it loops back to the 'pull'. However, upon returning to the 'pull' instead of allowing the user to input data, the program gets the bottom of data symbol '***'. This then of course causes an infinite loop and the user then can't put in data.

I believe the cause is displaying the panel, then using clrscrn. Cause i can take out clrscrn and it works fine but data truncates on other pages. Or i can sacrifice masking the user password by NOT displaying the ispf panel and it works. But together it fails.

I was wondering what is happening and the potential fix.

Rexx Code i use to replicate the error after displaying the panel:

do while chk <> 'N'
  clrscrn
  do i = 1 to 5
     say '-test'
  end
  pull chk
end

Result one with user input of ' '

-test
-test
-test
-test
-test
 ' '      <---- User inputs space, invalid entry, has to be 'N'
  ***      <-- for some reason hits bottom of data

Then it loops back with a result of:

-test
-test
-test
-test
-test
  ***    <---- automatically hits bottom of data

To reiterate, if i take out the clrscrn, bottom of data never occurs. but error too many times, data truncates to another page.

Put clrscrn back in, don't display an ispf panel. Code works flawlessly, bottom of data never occurs.

Panel code:

)PANEL
)ATTR
~  TYPE(INPUT) INTENS(NON) Pad(_)
!  TYPE(TEXT) COLOR(RED) SKIP(ON)
)BODY WINDOW(80,24)
!            CREATE YOUR PIN NUM
!--------------------------------------------
!
!            ENTER YOUR PIN:~INP !
!            CONFIRM PIN...:~INPT!
!
!             MUST BE 4-DIGITS
)END

Another panel I also call before similiar situations:

)PANEL
)ATTR
~  TYPE(INPUT) INTENS(NON) Pad(_)
!  TYPE(TEXT) COLOR(RED) SKIP(ON)
)BODY
!           VERIFY YOUR IDENTITY
!--------------------------------------------
!
!            ENTER YOUR PIN: ~Z   !
)INIT
&ZEDSMSG = ''
&ZEDLMSG = ''
.ZVARS = '( INP )'
.ATTR(INP)  = '&ATTRPIN'
)PROC
&RESP = .RESP
)END

Answer 1

The 3 asterisks indicate you have gone from full screen mode to line mode. The REXX say statement is line mode. You probably have a terminal using an alternate screen size (mod5, 62 x 160, etc). TSO VTAM will force the *** to protect against issues in changing between primary and alternate screen size. Use the following ISPF service instead of CLRSCRN

address ISPEXEC "CONTROL DISPLAY LINE START(1)"

This will put you in line mode and clear the screen. Your REXX routine works for me when I use the CONTROL DISPLAY LINE. This also tells ISPF that line mode has been entered which could also avoid screen corruption errors using CLRSCRN.