How to read one of the CBT AWS tapes

The CBT tape AWS images have a contents file as file one (1) on the tape.

As well as being a contents list it normally has the the tape contents including the file type (lrecl/blksize/recfm/dsorg etc) you will need to read each file off the tape; which is obviously usefull.

Nothing on the CBT tape site actually tells you how to read that first file off the tape. This is more for my reference as I don't keep index listings handy as I should so have to keep refering back to the aws tape contents... but this is how to read file one (1) off a CBT AWS tape image.

• the tape volser is normally the aws file name, ie: cbt072.aws should have volser cbt072
• the unit is the tape drive you attached the aws file to; for the example below a hercules user would have used 'devinit 480 cbt072.aws' (or something similar, there would generally be a directory path before the filename)
• The DCB information seems to have been standard since CBT tapes started shipping. So use it.
• note: If when you run the JCL below (I assume against a non-CBT tape as all the CBT tapes seem to be OK) the sysprint output says invalid record length, from past experience that really means the blocksize has changed; so look for some tape dump utilities :-)

//MARKSJOB JOB (0),'READ FIL1',MSGLEVEL=1,CLASS=A,MSGCLASS=T
//*
//* PRINT FILE 1 (CONTENTS) FROM A CBT TAPE
//*
//READFIL1 EXEC PGM=IEBGENER
//SYSPRINT DD   SYSOUT=*
//SYSIN    DD   DUMMY
//* VOLSER IS NORMALLY THE AWS FILE NAME
//* UNIT IS THE TAPE DEVICE YOU MOUNTED AWS TAPE ON
//SYSUT1   DD   VOL=SER=CBT072,UNIT=480,
// DISP=OLD,LABEL=(1,NL),
// DCB=(RECFM=FB,LRECL=80,BLKSIZE=32720)
//SYSUT2   DD   SYSOUT=*
//

For hercules users running turnkey3 the above JCL will print the contents of file one on the tape to the sysut2 output (class T is held output) that you can view using queue. Change the SYSUT2 sysout class if you want it to print.