zip file query

[Guest]

09-Jun-06

zip file query

In what way does a zip file save disk space - besides via compression?

Does the zip file actually remove all the original files from their original

locations on the drive and then compress them and store them all as a SINGLE
file back to a new location on disk?

If the latter is the case, then it would seem that in addition to space
savings via the compression route, there may be additional space saving
due to more efficient utilization of clusters (fewer clusters used).

What is the difference between winrar and winzip in the above regard?

T...

 

[Mac]

none, no, no idea...

 

[paulmd]

09-Jun-06

zip file query

In what way does a zip file save disk space - besides via compression?

Does the zip file actually remove all the original files from their original
locations on the drive and then compress them and store them all as a SINGLE
file back to a new location on disk?

No. Though you can do that later. A zip file is for archiving and
transporting files.

If the latter is the case, then it would seem that in addition to space
savings via the compression route, there may be additional space saving
due to more efficient utilization of clusters (fewer clusters used).

Slack space, you mean. Yes, some if you mean it creates a single file
versus multiples. Of course, this only applies if you delete the
originals after creating the archive.

What is the difference between winrar and winzip in the above regard?

Winrar has about 5% more compression than zip, for most file types.
Other than that, the principles are the same.

 

[Guest]

Do appreciate your reply - but I'd like to be 100% sure of exactly what's
happening here when I zip up several very small files. For example, it could
also be that each
compressed file within the zip file is assigned its own set of clusters, in
which case
there might still be some slack space for EACH of those files.

Have also queried WinZip and WinRar support but so far no answere. Let you
know.

Just occurred to me that a simple way to test this might be by checking how
many clusters are filled when zipping to a floppy - and see what the slack
space is. I suppose it should be less than one cluster, if we've assumed
correctly.

While I'm here, I think I might browse thru some of the other 'zip'-related
posts
to get a few more smarts on the subject. Never know...

Thanks again for your input,

 

[paulmd]

Do appreciate your reply - but I'd like to be 100% sure of exactly what's
happening here when I zip up several very small files. For example, it could
also be that each
compressed file within the zip file is assigned its own set of clusters, in
which case
there might still be some slack space for EACH of those files.

Have also queried WinZip and WinRar support but so far no answere. Let you
know.

Just occurred to me that a simple way to test this might be by checking how
many clusters are filled when zipping to a floppy - and see what the slack
space is. I suppose it should be less than one cluster, if we've assumed
correctly.

While I'm here, I think I might browse thru some of the other 'zip'-related
posts
to get a few more smarts on the subject. Never know...

Thanks again for your input,