[Info-vax] Fun with file attribrutes

[Jojimbo]

One of our programmers came to me for help reading a file that he had
received via SFTP.  This file had the records delimited by ~
characters.   Full directory information:

$ dir/full test.txt

Directory USERS:[USER.998]

TEST.TXT;1                    File ID:  (33285,3,0)
Size:        147KB/341KB      Owner:    [IDXUSER,USER]
Created:    23-DEC-2011 13:26:41.92
Revised:    23-DEC-2011 13:26:41.94 (1)
Expires:    <None specified>
Backup:     <No backup recorded>
Effective:  <None specified>
Recording:  <None specified>
Accessed:   <None specified>
Attributes: <None specified>
Modified:   <None specified>
Linkcount:  1
File organization:  Sequential
Shelved state:      Online
Caching attribute:  Writethrough
File attributes:    Allocation: 683, Extend: 0, Global buffer count: 0
                    No version limit
Record format:      Stream, maximum 0 bytes, longest 32767 bytes
Record attributes:  Carriage return 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, 147KB/341KB

I tried to read it in Python and got this result:

$ python
Python 2.7.2+ (default, Nov  7 2011, 14:45:22) [DECC] on OpenVMS
Type "help", "copyright", "credits" or "license" for more information.
>>> f = open('test.txt')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IOError: [Errno 65535] !ul byte record too large for user's buffer:
'test.txt'
<ctrl>Z

After fooling around for quite a while with convert and setting file
attributes I did this and was able to read the file and split it based
on the ~ characters no problem.

$ set file/attr=(rfm:udf,rat=none) test.txt
$ python
Python 2.7.2+ (default, Nov  7 2011, 14:45:22) [DECC] on OpenVMS
Type "help", "copyright", "credits" or "license" for more information.
>>> f = open('test.txt')
>>> s = f.read()

I then split the string s into records like:

>>> lines = s.split('~')

Which gave me an array (lines) that I could write out as a file.

Huh?  What did I do?  I guess as long as the file can fit into a
Python string then I'm OK.
But I find the whole thing puzzling but I am happy that it solved my
problem.

Regards, Jim