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(unix) mv across (ibm) ESS

$tinkle

Expert on blowing
Feb 12, 2003
14,591
6
getting conflicting information.

from the man pages:
If source and target_file/target_dir are on different file systems, mv copies the source and deletes the original.
yet ibm does not guarantee these results.

i s'pose i could just (s)cp them, then (rexec)rm them, but that's just eTarded.

anyone have any insight/experience w/ ESS?
 

binary visions

The voice of reason
Jun 13, 2002
22,092
1,132
NC
Hmm? I guess I don't understand the question?

Any *nix system I've ever worked with has a mv function that does what the man pages describe. What would the alternative be? Are you asking if it copies the file in its entirety before deleting any data?
 

$tinkle

Expert on blowing
Feb 12, 2003
14,591
6
an ESS may exist across multiple file systems, that's why they don't guarantee moving files, and certainly not atomically (i.e., it behaves more like a file xfer).

i've noticed even when moving files between directories on the same device it first moves a "shadow", then the file. i found this out w/ my application which essentially did this:
1: poll directory for file of interest
2: when found, mv to new loc, then notify
3: when notification received, open file in new loc

sticking a sleep(1) between 2 & 3 was the only way to guarantee i would always get a valid file handle (else, "file not found"). this happened rarely, but more than once meant the app wasn't meeting the terms of the contract.
 

binary visions

The voice of reason
Jun 13, 2002
22,092
1,132
NC
Ahh, I gotcha. Sorry, my experience with ESS is fairly limited - I got to play with a pretty large system @ an internship I did but it was a single filesystem.

You've had a few questions that have gone unanswered because they require technical expertise in a specific field. You may want to try the forums at AnandTech - there is a broader spectrum of very technical people over there.
 

$tinkle

Expert on blowing
Feb 12, 2003
14,591
6
thanks for the recommendation; if i can't find it there, it's b/c i got too tired to look.