running coz107, instead of creating half-track blocks, todsn still creates intermediate short blocks. Thus, Writting 8*27920=223360 bytes, an extra 9th block will be created. There seems to be no correlation with the file content. Writting a file containing all 'A' truncates at the same point as a file filled with '00'x...'ff'x.
Here are the first 6 blocks from RECFM=U,BLKSIZE=27998, RECFM=U,BLKSIZE=27920 and RECFM=VB,LRECL=27920,BLKSIZE=27924:
- >l dump maxlen(32)
PDS140I DUMP RECORD 1 LENGTH 27,998 TTR 000001
PDS140I DUMP RECORD 2 LENGTH 27,998 TTR 000002
PDS140I DUMP RECORD 3 LENGTH 27,998 TTR 000101
PDS140I DUMP RECORD 4 LENGTH 27,998 TTR 000102
PDS140I DUMP RECORD 5 LENGTH 19,080 TTR 000201
PDS140I DUMP RECORD 6 LENGTH 27,998 TTR 000202
>l dump maxlen(32)
PDS140I DUMP RECORD 1 LENGTH 27,920 TTR 000001
PDS140I DUMP RECORD 2 LENGTH 27,920 TTR 000002
PDS140I DUMP RECORD 3 LENGTH 27,920 TTR 000101
PDS140I DUMP RECORD 4 LENGTH 27,920 TTR 000102
PDS140I DUMP RECORD 5 LENGTH 19,392 TTR 000201
PDS140I DUMP RECORD 6 LENGTH 27,920 TTR 000202
>L DUMP MAXLEN(16)
PDS140I DUMP RECORD 1 LENGTH 27,924 TTR 000001
PDS140I DUMP RECORD 2 LENGTH 27,924 TTR 000002
PDS140I DUMP RECORD 3 LENGTH 27,924 TTR 000101
PDS140I DUMP RECORD 4 LENGTH 27,924 TTR 000102
PDS140I DUMP RECORD 5 LENGTH 19,416 TTR 000201
PDS140I DUMP RECORD 6 LENGTH 27,924 TTR 000202
Hope this makes sense,
best regards and have a nice Week-end
Jenö