wslu partial installation

wslu-partial.sh

#!/bin/sh

# Install parts of wslu (currently only wslview) as independent files to avoid
# installing the huge amount of dependencies.
# In Ubuntu 20.04-22.04 the dependecies are: 61 packages, 177 MB disk space

# Václav Brožík 2022-07
# public-domain

# references:
# https://github.com/wslutilities/wslu
# https://wslutiliti.es/wslu/

install_prefix=/usr/local

branch_url=https://raw.githubusercontent.com/wslutilities/wslu/dev/master
script_headers="$branch_url"/src/wslu-header
wslview_body="$branch_url"/src/wslview.sh
wslu_conf="$branch_url"/src/etc/conf

# browser registration:
# ---------------------
# wslview -r
# registers the following executable names using update-alternatives:
#   www-browser, x-www-browser

# applications using wslview:
# ---------------------------
# * without registration:
#    * gh
# * after registration (wslview -r):
#    * jupyter-lab

errexit () {
    printf '%s\n' "$*" Exiting. >&2
    exit 1
}

cat_url () {
    curl -fsSL "$@"
}

version="$(cat_url "$branch_url/VERSION")"

cat_url "$script_headers" "$wslview_body" |
        sed -e "s%PREFIXPLACEHOLDER%$install_prefix%" \
            -e "s/VERSIONPLACEHOLDER/$version/" |
        sudo dd of="$install_prefix/bin/wslview" ||
        errexit Failed to write wslview.
sudo chmod -v a+x "$install_prefix/bin/wslview" ||
        errexit Failed to chmod wslview.

sudo mkdir -vp "$install_prefix/share/wslu" ||
        errexit Failed to create directory.
cat_url "$wslu_conf" |
        sudo dd of="$install_prefix/share/wslu/conf" ||
        errexit Failed to write conf.