Identify comp/comp-3 data from file

bipinpeter · Posted: Thu Jan 14, 2016 2:27 pm

Hi All,

I am trying to read a file in rexx and trying to convert the data if fields are comp or comp-3.I have seen some of the thread for conversion.

I have the variables starting position and length but dont have type of the fields.I done substring on the record with start position and length and then did DATATYPE check.but always it will return type as CHAR.Is any way in rexx that can identify a field is comp or comp-3 field after reading from file.

Regards,
Bipin Peter

enrico-sorichetti · Posted: Thu Jan 14, 2016 2:55 pm

Willy Jensen · Posted: Thu Jan 14, 2016 2:58 pm

Hi, I'm not a COBOL person, but I understand that a comp-3 field is what in assembler is a packed decimal field.
A packed decimal field has the hex format X'nnnnns' where n must be a number and s is the sign C,D or F.
You can then identify a field to be comp-3 using something like the following:

u=c2x(substr(p,1,2)) /* pick field from record, convert to readable hex */
/* test for comp-3 */
if verify(left(u,3),'0123456789','N')=0,
& pos(right(u,1),'CDF')>0 then do /* comp-3 */
end
else do /* not comp-3 */
end

Willy

Bill Woodger · Posted: Thu Jan 14, 2016 4:15 pm

enrico-sorichetti · Posted: Thu Jan 14, 2016 4:22 pm

especially because the TS has asked

prino · Posted: Thu Jan 14, 2016 4:46 pm

You can do a bit of educated guesswork, but not much more, using:

length = 1: packed decimal or char
length = 2: all bets are off
length = 3: packed decimal or char
length = 4: all bets are off
length = 5/6/7/8: packed decimal or char
length > 8: most likely char

Of course if you use 64-bit comp-whatever binaries and 31 digit fixed decimals even more bets are off...

Willy Jensen · Posted: Thu Jan 14, 2016 5:09 pm

well, he did say 'I have the variables starting position and length' so I took it that he needed a test for comp3 or not comp3 (which is a 2-byte field as I understand). I agree that there could be something entire different in that area.

bipinpeter · Posted: Fri Jan 15, 2016 7:08 pm

Hi All,

I managed to get the type of data from the layout.

Now i am trying to convert the comp & comp-3 data to readable form.

One of my comp fields definition is PIC s9(07) comp.

Using substring I have taken the data and used C2X and X2D functions.

for this particular field, when i am viewing the data with fileaid I can see data as 1077990645.

After C2X function the compressed data got converted to 4040D4F5 but its giving error in X2D function.

Do you have any idea why this error happened and how we can do conversion?

Bipin Peter

Robert Sample · Posted: Fri Jan 15, 2016 7:38 pm

PIC S9(07) COMP will be a 4-byte hexadecimal value. X'4040D4F5' is 1077990645 in decimal. If you are seeing 1077990645 in File Aid, then the value is not being converted by your routines -- and I would suspect a problem with your layout since X'4040D4F5' is space space M 5 as zoned decimal DATA.