HP OpenVMS Systems

FTP file transfers and file formats?

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The Question is:

 
I copied a file last week between two nodes
running VMS V5.5-2 using FTP.
I then received a call from the user saying that
the download did not reflect the changes
expected.  I tried to run the enquiry myself
and received a "file not found" error, upon CQ
compilation.  The fix is pretty simple ... edit
the file and exit to create a new version - but
leads me to believe that the ftp has led to a
corruption to the file.
The only difference I can spot is that the ftp'd
file has a record format of "Variable length",
where as the 'fixed' file is "Variable length,
maximum 80 bytes"
This happens extremely frequently, when we
transfer files between the machines. Could you
please investigate and let me know if this can
be fixed.
 
 

The Answer is :

 
  You do not mention which IP package is in use, nor what version, nor
  if any ECO kits have been applied.
 
  Unlike format-independent transfer tools, FTP has two transfer modes:
  image (binary), and ASCII (text).  If the correct transfer mode is not
  selected, file problems can arise.
 
  FTP -- because it supports a variety of operating systems -- may or may
  not be able to transfer the file attributes exactly as expected.  The
  file data contents are not corrupted, though the file structure may or
  may not be exactly as expected -- and which can certainly be considered
  a form of file corruption.
 
  With TCP/IP Services for OpenVMS (UCX), consider using a recent version
  and the appropriate associated ECO kit, to get the latest version of FTP.
  Versions of UCX such as V4.1 -- while not supported on releases as far
  back as V5.5-2 -- have been used with success by some customers.
 
  One of the more common solutions in the UNIX space is to "zip" or "tar"
  the file before transfering it.  zip and tar are available for OpenVMS,
  as is BACKUP.  (BACKUP savesets can require issuing a SET FILE command,
  to reset the file attributes after an FTP transfer of the the saveset.)
 
  Alternatives include the use of DECnet and DECnet protocols -- DECnet
  COPY transfers handle the format transparently.  And for sites requiring
  IP, DECnet-Plus can operate over an IP transport, and can provide the
  capabilities and advantages and integration of DECnet in an IP network
  environment.
 
  If additional information or assistance is required, please contact
  the customer support center.
 

  

     

     
answer written or last revised on ( 3-SEP-1998 )
     
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