[Info-vax] Hard links on VMS ODS5 disks

[Johnny Billquist]

On 2023-07-15 16:04, Jan-Erik Söderholm wrote:
> Den 2023-07-15 kl. 15:32, skrev Craig A. Berry:
>>
>> On 7/14/23 9:58 PM, Dave Froble wrote:
>>> On 7/14/2023 9:48 PM, Craig A. Berry wrote:
>>>>
>>>> On 7/14/23 6:36 PM, Chris Townley wrote:
>>>>> On 14/07/2023 22:30, gah4 wrote:
>>>>
>>>>>> Reminds me of, years ago, porting gnu-utils to OS/2 and finding that
>>>>>> tail -f works.  I don't know if tail -f is supposed to work on 
>>>>>> VMS, though.
>>>>>>
>>>>>> The main target is embedded Linux, especially where the whole system
>>>>>> is in flash memory.
>>>>>
>>>>> But type/tail does ISTR
>>>>
>>>> On most of the interesting cases it fails with invalid file 
>>>> organization.
>>>>
>>>
>>> Works very well here.  Of course, I don't use invalid file 
>>> organizations.
>>>
>>> :-)
>>>
>>
>> I don't either, but the job controller does, and log files from batch
>> jobs are about the only reason I would use this feature. If memory
>> serves this is a well-known problem and somebody (maybe Hein?) had a fix
>> in the works that never got prioritized.
>>
>> $ type/tail somelogfile.log
>> %TYPE-W-OPENIN, error opening DSA0:[SOMEUSER]somelogfile.log;1 as input
>> -SYSTEM-E-UNSUPPORTED, unsupported operation or function
>> -RMS-F-ORG, invalid file organization value
>> $ dir/full somelogfile.log
>>
>> Directory DSA0:[SOMEUSER]
>>
>> somelogfile.log;1             File ID:  (9158,13,0)
>> Size:          900/912        Owner:    [SOMEGROUP,SOMEUSER]
>> Created:    15-JUL-2023 08:23:51.37
>> Modified:   15-JUL-2023 08:23:51.41 (1)
>> Expires:    <None specified>
>> Backup:     <No backup recorded>
>> Effective:  <None specified>
>> Recording:  <None specified>
>> Accessed:   15-JUL-2023 08:23:51.37
>> Attr Mod:   15-JUL-2023 08:23:51.41
>> Data Mod:   15-JUL-2023 08:23:51.37
>> Linkcount:  1
>> File organization:  Sequential
>> Shelved state:      Online
>> Caching attribute:  Writethrough
>> File attributes:    Allocation: 912, Extend: 0, Global buffer count: 
>> 0, No version limit
>> Record format:      VFC, 2 byte header, maximum 0 bytes, longest 1024 
>> bytes
>> Record attributes:  Print file carriage control
>> RMS attributes:     None
>> Journaling enabled: None
>> File protection:    System:RWED, Owner:RWED, Group:RE, World:
>> Access Cntrl List:  None
>> Client attributes:  None
>>
>> Total of 1 file, 900/912 blocks.
> 
> 
> As I have understood this (veruy annoying) thing is that
> the file org is not "invalid" as such, it is just not
> supported by type/tail...

Right.

And the secondary problem being that it's a little tricky to find the 
last n lines in such a file organization. You'll have to do some 
heuristics, and hope you got it right. But that usually is possible to 
do with a high chance of success. So it could definitely be done. (I 
have such a tool for RSX...)

   Johnny