[Info-vax] CRTL and RMS vs SSIO

[Arne Vajhøj]

On 10/6/2021 9:51 PM, Lawrence D’Oliveiro wrote:
> On Thursday, October 7, 2021 at 8:04:43 AM UTC+13, John Dallman wrote:
>> People used to UNIX or Windows generally find the other VMS file types
>> baffling and confusing.
> 
> One question I never saw answered (because I never came across
> examples of files to check it) was whether in “VFC” files, the record
> count included the fixed header or not? And was that the same or
> different in the on-disk format versus the in-memory RMS structure
> with the “RSZ” (“RAB$W_RSZ”?) field?

Try it!

$ open/write z.z z.z
$ write z.z "ABC"
$ close z.z
$ dir/full z.z

Directory DISK2:[ARNE]

z.z;1                         File ID:  (5295,236,0)
...
Record format:      VFC, 2 byte header, maximum 0 bytes, longest 3 bytes
...
$ dump z.z

Dump of file DISK2:[ARNE]z.z;1 on  6-OCT-2021 21:54:39.48
File ID (5295,236,0)   End of file block 1 / Allocated 16

Virtual block number 1 (00000001), 512 (0200) bytes

  00000000 00000000 00000000 00000000 00000000 0000FFFF 00434241 
8D010005 ....ABC......................... 000000

Arne