Can I zip an entire folder using gzip?

Question

I'm trying to zip a folder in unix. Can that be done using the gzip command?

Answer 1

No.

Unlike zip, gzip functions as a compression algorithm only.

Because of various reasons some of which hearken back to the era of tape drives, Unix uses a program named tar to archive data, which can then be compressed with a compression program like gzip, bzip2, 7zip, etc.

In order to "zip" a directory, the correct command would be

tar -zcvf archive.tar.gz directory/ 

This will tell tar to c (create) an archive from the files in directory (tar is recursive by default), compress it using the z (gzip) algorithm, store the output as a f (file) named archive.tar.gz, and v (verbosely) list (on /dev/stderr so it doesn't affect piped commands) all the files it adds to the archive.

The tar command offers gzip support (via the -z flag) purely for your convenience. The gzip command/lib is completely separate. The command above is effectively the same as

tar -cv directory | gzip > archive.tar.gz

To decompress and unpack the archive into the current directory you would use

tar -zxvf archive.tar.gz

That command is effectively the same as

gunzip < archive.tar.gz | tar -xv

tar has many, many, MANY other options and uses as well; I heartily recommend reading through its manpage sometime.

Answer 2

The gzip command will not recursively compress a directory into a single zip file, when using the -r switch. Rather it will walk that directory structure and zip each file that it finds into a separate file.

Example

before

$ tree dir1/
dir1/
|-- dir11
|   |-- file11
|   |-- file12
|   `-- file13
|-- file1
|-- file2
`-- file3

now run the gzip command

$ gzip -r dir1

after

$ tree dir1/
dir1/
|-- dir11
|   |-- file11.gz
|   |-- file12.gz
|   `-- file13.gz
|-- file1.gz
|-- file2.gz
`-- file3.gz

If you'd prefer to zip up the directory structure then you'll likely want to use the tar command, and then compress the resulting .tar file.

$ tar zcvf dir1.tar.gz dir1/

Example

$ tar zcvf dir1.tar.gz dir1/
dir1/
dir1/file1
dir1/file2
dir1/dir11/
dir1/dir11/file11.gz
dir1/dir11/file12.gz
dir1/dir11/file13.gz
dir1/file3

Which results in the following single file:

$ ls -l | grep tar
-rw-rw-r-- 1 saml saml  271 Oct  1 08:07 dir1.tar.gz

You can confirm its contents:

$ tar ztvf dir1.tar.gz 
drwxrwxr-x saml/saml         0 2013-10-01 08:05 dir1/
-rw-rw-r-- saml/saml         0 2013-10-01 07:45 dir1/file1
-rw-rw-r-- saml/saml         0 2013-10-01 07:45 dir1/file2
drwxrwxr-x saml/saml         0 2013-10-01 08:04 dir1/dir11/
-rw-rw-r-- saml/saml        27 2013-10-01 07:45 dir1/dir11/file11.gz
-rw-rw-r-- saml/saml        27 2013-10-01 07:45 dir1/dir11/file12.gz
-rw-rw-r-- saml/saml        27 2013-10-01 07:45 dir1/dir11/file13.gz
-rw-rw-r-- saml/saml         0 2013-10-01 07:45 dir1/file3

Answer 3

I scripted these 2 commands:

gzipdir:

#!/bin/bash
if [[ -d $1 ]]; then
    cd "$1"
    cd ..
    base=$(basename "$1")
    tar -zcvf "$base.tgz" "$base"
    if [[ $? == 0 && -f "$base.tgz" ]]; then
        rm -rf "$base"
    fi
else
    echo "Usage: $0 DIRECTORY";
fi

ungzipdir:

#!/bin/bash
if [[ -f $1 ]]; then
    base=${1%%.*}
    file=$(basename "$1");
    dir=$(basename "$base");
    if [[ ! -d $base ]]; then
        mkdir "$base"
        cd "$base"
        cd ..
        tar -xvf "$file"
        if [[ $? == 0 && -d "$dir" ]]; then
            rm -f "$file"
        fi
    else
        echo "Directory $base already exists. Nothing done."
    fi
else
    echo "Usage: $0 file.tgz";
fi

(!!!) Please test before use (as there is a 'rm -f' which could potentially remove important data if used in an uncommon way).

How to use

cd /home/; gzipdir MyDirectory or gzipdir /home/MyDirectory

Will create /home/MyDirectory.tgz and remove MyDirectory on success (!!!).

gunzipdir /home/MyDirectory.tgz

Will create /home/MyDirectory and remove /home/MyDirectory.tgz on success.

Answer 4

If your linux tar doesn't support the -z option you can use the following:

tar -cvf - dir | gzip > dir.tar.gz

Answer 5

I recommend using pigz(Parallel Implementation of GZip)

tar -cvf - dir | pigz -9 > /path/to/dir.tar.gz

Answer 6

The Answer to the question “Can I zip an entire folder using gzip?” is to use the syntax:

zip -r <zip file name> <folder to zip>