criteria to decide non-printable character for cobol

Viplav Modi · New User Joined: 23 Jan 2013 Posts: 2 Location: India

Hello everyone,

This is my first post and I am a little scared to post a new topic as I am only going to dig something which has already been discussed in past several times so please accept my apologies in advance before I go forward and post my query.

This is with reference to the post COBOL NON PRINTABLE CHARACTERS
(http://ibmmainframes.com/about45429-0-asc-15.html).
As suggested by Ronald blur we can achieve this by coding two 256-byte working storage elements ..........
Using the code mentioned in that post I am able to change non-printable to characters to spaces.
Here as per the source and target table mapping I can see x'BA' which is character '[' getting replaced by x'40' (spaces). As per my understanding this '[' shouldn't be non-printable for cobol.
I tried to enter some of the source characters in a file to check how they will look like and figured out that this table mapping would replace some of the symbols (for ex:^ ) to spaces.
My query is on what basis we can decide a character is non-printable for cobol or not?

enrico-sorichetti · Posted: Thu Apr 11, 2013 12:53 pm

Bill Woodger · Posted: Thu Apr 11, 2013 1:38 pm

As enrico alludes, only you can tell what is/is not "displayable" for your requirement.

Take a 256-byte table of 00 to FF. Display it in HEX and "character" simultaneously. On your "output" mark off/note the hex values for the things you want to exclude (or include, probably, as there will be fewer, likely). Amend the program.

Viplav Modi · New User Joined: 23 Jan 2013 Posts: 2 Location: India

Thanks alot for such a quick response Enrico and Bill .
So far all I know is that x'12' is invalid/bad character/non-printable in my case. As per my requirement I am replacing this x'12' with apostrophe(').
But then the complete requirement states that other than this x'12' rest of the non-printable characters should be replaced by spaces.
It is not mentioned anywhere as what other characters are non-printable.

As enrico pointed out that a character is printable/non-printable according to the DEVICE used so I will try to figure out which device is being used here.

enrico-sorichetti · Posted: Thu Apr 11, 2013 3:04 pm

but apart the <hardware> capabilities
You should also keep in mind the APPLICATION point of view
not alway what You can print/display is valid for the APPLICATION

Marso · Posted: Thu Apr 11, 2013 6:21 pm

Maybe you should consider READABLE instead of PRINTABLE.
You have to decide if chars from B0 to BF are just "noise" or are worth the ink.

Jose Mateo · Posted: Thu Apr 11, 2013 7:08 pm

Good day to all!

You have misunderstood Enrico on code-page. Code-page is not a device. Read on code-page so you could understand what Enrico is telling you.