`gzip` - compress or expand files

gzip [-c] [-d] [-k] FILE...

Options you will use

-c: write to standard output, keep the original
-d: decompress (= gunzip)
-k: keep the input files
-c, --stdout: write on standard output, keep original files unchanged
-d, --decompress: decompress
-f, --force: force overwrite of output file and compress links
-k, --keep: keep (don't delete) input files
-l, --list: list compressed file contents (compressed and uncompressed size, ratio)
-t, --test: test compressed file integrity
-v, --verbose: verbose mode
-1, --fast: compress faster
-9, --best: compress better
-h, --help: give this help
-V, --version: display version number

$ pg_dump orders | gzip > orders.sql.gz

a compressed plain dump

$ gzip -k big.log

compress, keep the original

$ gzip -l orders.sql.gz

sizes and ratio

$ gzip -t orders.sql.gz

is the file intact?

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