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How to gzip and keep original file on Unix or Linux command line

I would like to compress a log file using gzip Unix command line utility, and I would also like to keep the original file. However, when I use the gzip my-app.log command, results in modifying my log file and renaming it my-app.log.gz. How do I force the gzip command to keep original file while maintaining the original file on Linux or Unix-like system?

The gzip program compresses and decompresses files on Unix like system. You need to pass the -c or --stdout, or --to-stdout option to the gzip command. This option specifies that output will go to the standard output stream, leaving original files intact.

Syntax: To keep original file while using gzip

The options are as follows:

gzip -c input.file > output.file.gz

If no files are specified and in direction used, gzip will compress from standard input, or decompress to standard output. So one can use the following syntax:

gzip < input.file > output.file.gz

Or pass the -k/--keep to the gzip command to leep (don’t delete) input files during compression or decompression:

gzip -k input.file
gzip --keep input.file

Examples

Let us tell gzip command to keep original file called Friday-Comic.jpg :

$ ls -lh Friday-Comic.jpg

Gzip and create a new file called Friday-Comic-1.jpg.gz:

$ gzip -c Friday-Comic.jpg > Friday-Comic-1.jpg.gz
$ ls -lh Friday-Comic-1.jpg.gz

Gzip and create a new file called Friday-Comic-1.jpg.gz using shell redirection:

$ gzip < Friday-Comic.jpg > Friday-Comic-2.jpg.gz
$ ls -lh Friday-Comic*