'cp' and slack space

viRaven · #1 (**permalink**) 05-16-2007

Does the 'cp' command copy the slack space of the copied file to the new location(e.g. CDROM, TAPE)?

I've read that slack space is only copied in a bitstream copy/backup. Is the 'cp' utility a bitstream copy?

sysgate · #2 (**permalink**) 05-17-2007

This is a good question, actually, each filesystem has its own rules for slack space. Let's consider UFS or ext3, as they act the same in this meaning :

Quote:

By default, sparse SOURCE files are detected by a crude heuristic and the corresponding DEST file is made sparse as well. That is the behavior selected by --sparse=auto. Specify --sparse=always to create a sparse DEST file whenever the SOURCE file contains a long enough sequence of zero bytes. Use --sparse=never to inhibit creation of sparse files.

where sparse files are a type of computer files that attempt to use file system space more efficiently; so, "cp" by default doesn't use slack space, means , it's optimized for work.

Other UNIX.COM Threads You Might Find Helpful
Thread	Thread Starter	Forum	Replies	Last Post
Pb with space wc -l	francis_tom	Shell Programming and Scripting	4	04-13-2008 12:44 PM
SLACK 0.15.0 (Default branch)	iBot	Software Releases - RSS News	0	01-16-2008 03:50 AM
space hog	afflack	UNIX for Dummies Questions & Answers	5	01-27-2005 04:14 PM
swap space / paging space	aaronh	AIX	2	05-19-2004 07:06 AM
pageing space vs swap space	VeroL	UNIX for Dummies Questions & Answers	1	01-22-2004 07:54 AM

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode