08-28-2013
Quote:
Originally Posted by
filosophizer
Now, if someone wants to check how much space is needed to untar and uncompress the file oraclebackup.tgz how can he check ?
You can't: because of he algorithm used there is no direct relation between the source and the target file size: if file X is bigger than file Y then X.gz might still be smaller than Y.gz. The only way to find out is to actually compress the file. The same is true for the other way round.
I hope this helps.
bakunin
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
I'm trying to set up a stanard sh script that will find all the files that have been changed within the last day and then tar them up.
I think the command line should be something like :
find /home/bob -atime +0 -exec \ tar cvf /home/bob/files.tar {}\;
Help please ...
Thanx (3 Replies)
Discussion started by: ianf
3 Replies
2. UNIX for Dummies Questions & Answers
# grep "Jul 3" syslog.messages | more
Jul 3 00:16:03 www3 CPU3: NOTICE: HTFS: No space on dev hd (1/42)
Jul 3 00:16:08 www3 CPU3: NOTICE: HTFS: No space on dev hd (1/42)
Jul 3 00:17:01 www3 CPU2: NOTICE: HTFS: No space on dev hd (1/42)
Jul 3 00:17:06 www3 syslogd: /usr/adm/debug: No space... (1 Reply)
Discussion started by: Cameron
1 Replies
3. UNIX for Dummies Questions & Answers
Hi,
I am creating a disaster recovery plan for my Linux 7.2 machine. I have two backups from my current machine.
One created using the command
tar -cvpf /dev/st0 --exclude=/proc --directory / .
and one created with the command
find / /boot /home -mount -path '/proc' -prune -o -print |... (4 Replies)
Discussion started by: jeremiebarber
4 Replies
4. UNIX for Dummies Questions & Answers
Hi,
I've got dozens of tar's with two files in each one,
live_access_log & live_error_log (one tar for each day, backups).
The probelm is i need to match a pattern in all of the archive_access_log files and output the line to a seperate file (All_access.log).
I.e. I need to get details... (21 Replies)
Discussion started by: tom123
21 Replies
5. Solaris
Hi all,
I would like to know what would happen if the tape (media) is not placed on the drive and a tar command is executed to backup on the tape.
My problem is that tar command hanged for multiple days instead of throwing the error,
Is it valid behaviour?
I was unable to test the... (4 Replies)
Discussion started by: jmsathish
4 Replies
6. Shell Programming and Scripting
Hiiiii friends
I have 2 files which contains huge data & few lines of it are as shown below
File1: b.dat(which has 21 columns)
SSR 1976 8 12 13 10 44.00 39.0700 70.7800 7.0 0 0.00 0 2.78 0.00 0.00 0 0.00 2.78 0 NULL
ISC 1976 8 12 22 32 37.39 36.2942 70.7338... (6 Replies)
Discussion started by: reva
6 Replies
7. Solaris
Hi Gurus
I need to know few things related to HBA port & fcinfo command
I have a server where there are 4 HBA ports cards are their. Out of 4 ports 2 are in use & 2 are not in use when I check it physicall. Now I want to know the command through which I can get information about all above... (6 Replies)
Discussion started by: girish.batra
6 Replies
8. AIX
Steps to upgrade AIX TL ( technology Level ) / Maintenance Level in AIX ( including Firmware HMC VIOS )
This article or post covers upgrades for
- Hardware Management Console ( HMC )
- Firmware ( also known as microcode )
- VIO ( Virtual I/O Server = PowerVM )
- AIX Version, Technology... (2 Replies)
Discussion started by: filosophizer
2 Replies
9. Shell Programming and Scripting
Need to
1. archive all the files in a directory from the previous month into a tar/gz file, ignoring all already archived 'tar.gz' files
2. Check created .tar.gz file isnt corrupted and has all the required files in it. and then remove the original files.
I am using a function to get the... (1 Reply)
Discussion started by: Prev
1 Replies
10. AIX
Hello,
Getting this very strange error, made tar/zip through gnu tar
GNU Tar ( successful tar and zip without any errors )
/opt/freeware/bin/tar cvf - /oraapp| gzip > /backup/bkp_15_6_16_oraapp.tgz
GNU unTar error
root@test8:/>gunzip < /config1/bkp_15_6_16_oraapp.tgz |... (5 Replies)
Discussion started by: filosophizer
5 Replies
LEARN ABOUT ULTRIX
compress
compress(1) General Commands Manual compress(1)
Name
compress, uncompress, zcat - compress and expand data
Syntax
compress [ -f ] [ -v ] [ -c ] [ -b bits ] [ name ... ]
uncompress [ -f ] [ -v ] [ -c ] [ name ... ]
zcat [ name ... ]
Description
The command reduces the size of the named files using adaptive Lempel-Ziv coding. Whenever possible, each file is replaced by one
with the extension .Z, while keeping the same ownership modes, access, and modification times. If no files are specified, the
standard input is compressed to the standard output. Compressed files can be restored to their original form using or
The -f option will force compression of name, even if it does not actually shrink name, or if the corresponding name .Z file
already exists. If the -f option is omitted, the user is asked whether an existing name.Z file should be overwritten (unless is
run in the background under
The -c (cat) option makes compress/uncompress write to the standard output without changing any files. Neither -c nor alter files.
The command uses the modified Lempel-Ziv algorithm. Common substrings in the file are first replaced by 9-bit codes 257 and up.
When code 512 is reached, the algorithm switches to 10-bit codes and continues to use more bits until the limit specified by the -b
flag is reached (default 16). The bits must be between 9 and 16. The default can be changed in the source to allow to be run on a
smaller machine.
After the bits limit is attained, periodically checks the compression ratio. If the ratio is increasing, continues to use the
existing code dictionary. However, if the compression ratio decreases, discards the table of substrings and rebuilds it from
scratch. This allows the algorithm to adapt to the next block of the file.
Note that the -b flag is omitted for since the bits parameter specified during compression is encoded within the output along with
a number that ensures that neither decompression of random data nor recompression of compressed data is attempted.
How much each file is compressed depends on the size of the input, the number of bits per code, and the distribution of common sub-
strings. Typically, text such as source code or English is reduced by 50-60%. Compression is generally much better than that
achieved by Huffman coding or adaptive Huffman coding, and takes less time to compute.
The -v option displays the percent reduction of each file.
If an error occurs, exit status is 1. However, if the last file was not compressed because it became larger, the status is 2.
Otherwise, the status is 0.
Options
-f Forces compression of name.
-c Makes compress/uncompress write to the standard output.
-b Specifies the allowable bits limit. The default is 16.
-v Displays the percent reduction of each file.
Diagnostics
Usage: compress [-fvc] [-b maxbits] [file ...]
Invalid options were specified on the command line.
Missing maxbits
Maxbits must follow -b.
file: not in compressed format
The file specified to uncompress has not been compressed.
file: compressed with xx bits, can only handle yy bits
The file was compressed by a program that could deal with more bits than the compress code on this machine. Recompress the file
with smaller bits.
file: already has .Z suffix -- no change
The file is assumed to be compressed already. Rename the file and try again.
file already exists; do you wish to overwrite (y or n)?
Type y if you want the output file to be replaced; type n if you do not.
uncompress: corrupt input
A SIGSEGV violation was detected which usually means that the input file is corrupted.
Compression: xx.xx%
Percent of the input saved by compression. (For the -v option only.)
-- not a regular file: unchanged
If the input file is not a regular file (for example, a directory), it remains unchanged.
-- has xx other links: unchanged
The input file has links; it is left unchanged. See for more information.
-- file unchanged
No savings is achieved by compression. The input remains unchanged.
Restrictions
Although compressed files are compatible between machines with large memory, -b12 should be used for file transfer to architectures
with a small process data space (64KB or less).
RISC compress(1)