gzip vs pipe gzip: produce different file size


 
Thread Tools Search this Thread
Top Forums UNIX for Advanced & Expert Users gzip vs pipe gzip: produce different file size
Prev   Next
# 1  
Old 06-03-2011
gzip vs pipe gzip: produce different file size

Hi All,

I have a random test file: test.txt, size: 146
$ ll test.txt
$ 146 test.txt

Take 1:
$ cat test.txt | gzip > test.txt.gz
$ ll test.txt.gz
$ 124 test.txt.gz

Take 2:
$ gzip test.txt
$ ll test.txt.gz
$ 133 test.txt.gz

As you can see, gzipping a file and piping into gzip produce different sized *gz files. The problem currently is that some archivers, such as WinZip and Cygwin's gunzip have to unzip the piped gzip file twice before it can be read as a plain text file. Why is this and how can I ensure piping into gzip produces the same file as gzipping a file?

Thanks,
 
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

MIME type for sending gzip file as attachment in email

Hello, I am trying to send a gzip file on email using below command but the zipped file received on email is corrupt. mailsend -smtp $smtpip -content-type 'application/x-gzip' -mime-type "application/x-gzip" -t $receiver -f $sender -sub "$subject" -M "$MSG" -attach $file file name is ... (1 Reply)
Discussion started by: tushar.modgil
1 Replies

2. Shell Programming and Scripting

Shell script not able to zip the file using gzip

Hi all, I am calling Temp.sh and it is has simple line $gpath=`which gzip` $gpath $FilePath/My_temp.log if I run this script, logging to server then its works fine. But when I send this script over the SSH it does not work at it. gzip is command is not execute. I am using gzip 1.6... (2 Replies)
Discussion started by: girijajoshi
2 Replies

3. Shell Programming and Scripting

File name manipulation when extracting from gzip

Hi, Below is the description of my problem. I am trying to loop through the below file names sitting in the file - FileNames.txt, and trying to decompress them FileNames.txt 20150408_MGAC_.txt.gz 20150408_MGCC_.txt.gz 20150408_MGSH__.txt.gz 20150408_MGSL__.txt.gz ... (6 Replies)
Discussion started by: Richmond_CS
6 Replies

4. Shell Programming and Scripting

Check if file is locked otherwise gzip it

Dear community, I've a continuos tcpdump on redhat that close the dumped file every 100000 captured packets. To avoid disk full I would like to gzip the closed *.cap file. But how can I check if the file is currently opened by tcpdump and skip it from gzip? Thanks! EDIT: Just to post an... (9 Replies)
Discussion started by: Lord Spectre
9 Replies

5. UNIX for Dummies Questions & Answers

gzip of a file in the same folder

I want gzip of a file in the same folder where it is kept now $filename = '/var/dev/test.txt' /opt/home/>> gzip -c $filename > test.txt.gz however command creates it in the folder in /opt/home/ How to gzip a file in the same directory where it is now , no matter from where we execute and also... (2 Replies)
Discussion started by: lalitpct
2 Replies

6. Programming

gzip on pipe error handling

Hi all... I have the following code: FILE *fp = popen(" gzip -dc /somemount/somefile.gz", "r"); while(fgets(buffer, 1024, fp)) { some code.... } "/somemount" is a mount of some network drive. Sometimes error occurs in while loop - I can see the following "Input/Output error"... (4 Replies)
Discussion started by: adm1n
4 Replies

7. Shell Programming and Scripting

Appending a GZIP File

Guys, I just want to know the difference in following (core difference) zcat a.gz b.gz c.gz |gzip >d.gz And zcat a.gz >>d.gz zcat b.gz >>d.gz zcat c.gz >>d.gz do we have 3 gzip header in 1st and only one in second case. please let me know this in detail Thanks,... (2 Replies)
Discussion started by: mohan_xunil
2 Replies

8. Solaris

gzip a file and append creation date stamp to file

I want to gzip a file and append the creation date to the end of the file. How can I accomplish this task. Basically they are log files which need a creation date stamp appended to make sure they do not overwrite other log files. -jack (3 Replies)
Discussion started by: jacktravine
3 Replies

9. Solaris

script for Gzip thousands of file

Hi experts, I have thousands of file (data file and Gziped file) in same directory like below-- bash-2.05$ pwd /home/mmc bash-2.05$ file PP023149200709270546 TT023149200709270546: gzip compressed data - deflate method bash-2.05$ file PP027443200711242320 TT027443200711242320: ... (10 Replies)
Discussion started by: thepurple
10 Replies

10. UNIX for Dummies Questions & Answers

How do I send a file as an attachment (gzip file) on a Unix system

Hi, How do I send a file as an attachment (gzip file) on a Unix system ? Using sendmail. Please help me. :confused: (3 Replies)
Discussion started by: lacca
3 Replies
Login or Register to Ask a Question
ZIPARCHIVE.OPEN(3)							 1							ZIPARCHIVE.OPEN(3)

ZipArchive::open - Open a ZIP file archive

SYNOPSIS
mixed ZipArchive::open (string $filename, [int $flags]) DESCRIPTION
Opens a new zip archive for reading, writing or modifying. PARAMETERS
o $filename - The file name of the ZIP archive to open. o $flags - The mode to use to open the archive. o ZipArchive::OVERWRITE o ZipArchive::CREATE o ZipArchive::EXCL o ZipArchive::CHECKCONS RETURN VALUES
o $Error codes - Returns TRUE on success or the error code. o ZipArchive::ER_EXISTS File already exists. o ZipArchive::ER_INCONS Zip archive inconsistent. o ZipArchive::ER_INVAL Invalid argument. o ZipArchive::ER_MEMORY Malloc failure. o ZipArchive::ER_NOENT No such file. o ZipArchive::ER_NOZIP Not a zip archive. o ZipArchive::ER_OPEN Can't open file. o ZipArchive::ER_READ Read error. o ZipArchive::ER_SEEK Seek error. EXAMPLES
Example #1 Open and extract <?php $zip = new ZipArchive; $res = $zip->open('test.zip'); if ($res === TRUE) { echo 'ok'; $zip->extractTo('test'); $zip->close(); } else { echo 'failed, code:' . $res; } ?> Example #2 Create an archive <?php $zip = new ZipArchive; $res = $zip->open('test.zip', ZipArchive::CREATE); if ($res === TRUE) { $zip->addFromString('test.txt', 'file content goes here'); $zip->addFile('data.txt', 'entryname.txt'); $zip->close(); echo 'ok'; } else { echo 'failed'; } ?> PHP Documentation Group ZIPARCHIVE.OPEN(3)