Updates the lwjgl that minecraft uses.

update_lwjgl.sh

#!/usr/bin/env bash

echo "Determining OS..."

if [[ "$(uname -s)" == "Linux" ]]; then
    mcdir="$HOME/.minecraft/"
    downloader="wget --no-check-certificate -q -O"
    os="linux"
    natives="libjinput-linux libjinput-linux64 liblwjgl liblwjgl64 libopenal libopenal64"
elif [[ "$(uname -s)" == "Darwin" ]]; then
    mcdir="$HOME/Library/Application\ Support/minecraft/"
    downloader="curl -o"
    os="macosx"
    natives="libjinput-osx.jnilib liblwjgl.jnilib openal.dylib"
else
    echo "OS not supported.  Exploding..."
    exit 1
fi

echo "Determining installed LWJGL version..."

installed="$(unzip -p $mcdir/bin/lwjgl.jar | strings | grep  '^[0-9]*\.[0-9]*\.[0-9]*')"

echo "LWJGL $installed installed"

echo "Determining latest online version..."

latest=$(${downloader%%-o} - http://lwjgl.org/download.php |\
        grep -oE  "https?:\/\/sourceforge.net\/projects\/java-game-lib\/files\/Official%20Releases\/LWJGL%20[0-9|\.]*")

echo "Found version ${latest##*%20}"

if [[ "${latest##*%20}" == "$installed" ]]; then
    echo "LWJGL already at current version."
    if [[ "$1" == "-force" ]]; then
        echo "Updating anyways..."
    else
        exit 0
    fi
fi

echo "Determining download URL..."

dlurl=$(${downloader%%-o} - "$latest" |\
        grep -oE -m1 "https?://sourceforge.net/projects/java-game-lib/files/Official%20Releases/LWJGL%20[0-9|\.]*/lwjgl-[0-9|\.]*.zip")

echo "Checking if ~./cache/ exists..."

if [[ ! -d "$HOME/.cache/" ]]; then
    echo "~/.cache/ did not exist.  Creating..."
    mkdir "$HOME/.cache/"
fi

echo "Downloading latest LWJGL..."

$downloader "$HOME/.cache/lwjgl.zip" "$dlurl"

echo "Extracting zip file..."

unzip -qqo "$HOME/.cache/lwjgl.zip" -d "$HOME/.cache/"

lwjgldir=$(find -L "$HOME/.cache" -maxdepth 1 -type d -name "*lwjgl*" -print)
echo "Copying files..."

for i in "jinput" "lwjgl" "lwjgl_util"; do
    echo "Copying $i..."
    cp "$lwjgldir/jar/$i.jar" "$mcdir/bin/"
done
for i in $natives; do
    echo "Copying $i..."
    cp "$lwjgldir/native/$os/$i.so" "$mcdir/bin/natives/"
done

echo "Deleting cache..."

rm -rf "$lwjgldir"

Change line 62 to lwjgldir=$(find -L "$HOME/.cache" -maxdepth 1 -type d -name "lwjgl" -print)

This way if your home directory has a symbolic link for .cache (I have a symbolic link there for speed), find correctly points to the lwjgl directory extracted by unzip.

I've updated the script accordingly. thanks!

It's great to see more people and scripts using XDG dirs like ~/.config, ~/.local, ~/.cache, etc to unclutter user's $HOME, so kudos for that! And, if you want to further improve that, use cachedir=${XDG_CACHE_HOME:-"$HOME/.cache"} instead of hardcoding "$HOME/.cache". Remember all XDG dirs are configurable via env vars, and ~/.cache is just a default. Also, setting this value in a cachedir var somewhere near the top will allow you to avoid repeating it over and over through the code..

Make sure you run it as bash, I used "sh" and on my Kubuntu that's symlinked to dash (I didn't realise). That gives a couple of errors on the [[ tests. using "bash update.sh" worked fine, thanks.

Updated your script

• fix no longer working URLs
• Removed grep dependency
• Added check for unzip availability
• Hardened code style
  TODO: check download and unzip success and exit with error message if it fail

#!/usr/bin/env bash

# Exit on error. Append "|| true" if you expect an error.
set -o errexit
# Exit on error inside any functions or subshells.
set -o errtrace
# Do not overwrite an existing file with the >, >&, and <> redirection operators.
set -o noclobber
# Do not allow use of undefined vars. Use ${VAR:-} to use an undefined VAR
set -o nounset
# Pipeline's return status is the value of the last (rightmost) command
# to exit with a non-zero status, or zero if all commands exit successfully.
set -o pipefail

if ! which unzip; then
  echo >&2 "the 'unzip' utility is required!"
  exit 1
fi

echo 'Determining OS...'

declare __unames
__unames="$(uname -s)"
declare __mcdir
declare __os
declare __downloader
declare -a __natives
if [[ "${__unames}" == "Linux" ]]; then
  __mcdir="${HOME}/.minecraft/"
  __downloader='wget --no-check-certificate -q -O'
  __os='linux'
  __natives=(
    'libjinput-linux'
    'libjinput-linux64'
    'liblwjgl'
    'liblwjgl64'
    'libopenal'
    'libopenal64'
  )
elif [[ "${__unames}" == "Darwin" ]]; then
  __mcdir="${HOME}/Library/Application Support/minecraft/"
  __downloader='curl -o'
  __os='macosx'
  __natives=(
    'libjinput-osx.jnilib'
    'liblwjgl.jnilib'
    'openal.dylib'
  )
else
  echo >&2 'OS not supported.  Exploding...'
  exit 1
fi

echo 'Determining installed LWJGL version...'

[[ "$(
  unzip -p "${__mcdir}/bin/lwjgl.jar" 'org/lwjgl/Sys.class' | strings
)" =~ [0-9]+\.[0-9]+\.[0-9]+ ]]
declare __installed="${BASH_REMATCH[0]}"

echo "LWJGL ${__installed} installed"

echo 'Determining latest online version...'

[[ "$(
  ${__downloader%%-o} - 'http://legacy.lwjgl.org/download.php.html'
)" =~ https?://sourceforge.net/projects/java-game-lib/files/Official%20Releases/LWJGL%20[0-9|\.]* ]]
declare __latest="${BASH_REMATCH[0]}"

echo "Found version ${__latest##*%20}"

if [[ "${__latest##*%20}" == "${__installed}" ]]; then
  echo >&2 'LWJGL already at current version.'
  if [[ "${1:-}" == "-force" ]]; then
    echo 'Updating anyways...'
  else
    exit 0
  fi
fi

echo 'Determining download URL...'

[[ "$(
  ${__downloader%%-o} - "${__latest}"
)" =~ https?://sourceforge.net/projects/java-game-lib/files/Official%20Releases/LWJGL%20[0-9|\.]*/lwjgl-[0-9|\.]*.zip ]]
declare __dlurl="${BASH_REMATCH[0]}"

echo "Checking if ${HOME}/.cache/ exists..."

if [[ ! -d "${HOME}/.cache/" ]]; then
  echo "${HOME}/.cache/ did not exist.  Creating..."
  mkdir "${HOME}/.cache/"
fi

echo 'Downloading latest LWJGL...'

${__downloader} "${HOME}/.cache/lwjgl.zip" "${__dlurl}"

echo 'Extracting zip file...'

unzip -qqo "${HOME}/.cache/lwjgl.zip" -d "${HOME}/.cache/"

declare __lwjgldir
__lwjgldir="$(find -L "${HOME}/.cache" -maxdepth 1 -type d -name "*lwjgl*" -print)"
echo 'Copying files...'

for i in 'jinput' 'lwjgl' 'lwjgl_util'; do
  echo "Copying ${i}..."
  cp "${__lwjgldir}/jar/${i}.jar" "${__mcdir}/bin/"
done
for i in "${__natives[@]}"; do
  echo "Copying ${i}..."
  cp "${__lwjgldir}/native/${__os}/${i}.so" "${__mcdir}/bin/natives/"
done

echo 'Deleting cache...'

find "${__lwjgldir}" -delete