Update 10/12/2014:

As suggested by stan, a file-system with transparent compression should be a much easier, and overall better, option for on-the-fly game decompression. You can get this through a fuse-based file-system like fusecompress, or natively if you have a btrfs partition.

Original Post:

Some might find this useful, especially if you, like me, enjoy maximizing space usage efficiency.

I've been working on ways to maintain the more compressible games in my collection in archives, and decompress them on-the-fly when I want to play them. In a way similar to how some emulators treat ROMs in zip files.

Originally I was just making use of the /tmp/ folder, but I figured having to decompress things at least once in a session is a bit of an IO waste, especially if I was using an SSD. So I decided to make a cache for it, and I just released it on github:

https://github.com/ntfwc/decompression_cache

I'm currently using it with 9 games on my system and with an emulator, to add archived ISO support to it. I've been pretty happy with the results. And it could have applications in other more general tasks, as well.

I'll put two example wrapper scripts below. One for a game and one for an emulator:

Cave Story+ Wrapper:
#!/bin/bash
ARCHIVE=/home/ntfwc/Games/CaveStory+/CaveStory+.tar.gz
EXPECTED_OUTPUT_DIR=CaveStory+
DECOMPRESSED_CONTENT_DIR=$(/home/ntfwc/Programs/cached_decompression/cached_decompress "$ARCHIVE" )

cd $DECOMPRESSED_CONTENT_DIR/$EXPECTED_OUTPUT_DIR
./CaveStory+_64

PCSX Emulator Wrapper:
#!/bin/bash
GAME=$1

#Get the filename without the archive extension
FILENAME=$(basename "$GAME" )
OUTPUT_FILE=${FILENAME%.*}

DECOMPRESSED_CONTENT_DIR=$(/home/ntfwc/Programs/cached_decompression/cached_decompress "$GAME" )

OUTPUT_PATH="$DECOMPRESSED_CONTENT_DIR/$OUTPUT_FILE"
pcsx -nogui -cdfile "$OUTPUT_PATH"

Edit: Darn smilies.