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try add minimdnsd
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‎.DS_Store

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‎.github/workflows/minimdnsd.yml

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---
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on:
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push:
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branches:
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- main
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paths:
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- .github/workflows/minimdnsd.yml
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- minimdnsd/**
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jobs:
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minimdnsd:
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runs-on: ubuntu-latest
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steps:
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- name: Checkout
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uses: actions/checkout@v2
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with:
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submodules: true
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- name: Login
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uses: docker/login-action@v1
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with:
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username: ${{ secrets.DOCKER_HUB_USERNAME }}
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password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
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- name: Setup QEMU
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uses: docker/setup-qemu-action@v1
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- name: Setup Docker
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uses: docker/setup-buildx-action@v1
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- name: Build Docker
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uses: docker/build-push-action@v2
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with:
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push: true
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context: ${{ github.job }}
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file: ${{ github.job }}/Dockerfile
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platforms: linux/amd64
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tags: ${{ secrets.DOCKER_HUB_USERNAME }}/${{ github.job }}:latest
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cache-from: type=registry,ref=${{ secrets.DOCKER_HUB_USERNAME }}/${{ github.job }}:buildcache
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cache-to: type=registry,ref=${{ secrets.DOCKER_HUB_USERNAME }}/${{ github.job }}:buildcache,mode=max
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- name: Push Docker Description
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uses: peter-evans/dockerhub-description@v2
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with:
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username: ${{ secrets.DOCKER_HUB_USERNAME }}
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password: ${{ secrets.DOCKER_HUB_PASSWORD }}
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repository: ${{ secrets.DOCKER_HUB_USERNAME }}/${{ github.job }}
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short-description: '使用参考 README，信息参考：https://www.dosk.win/'

‎minimdnsd/Dockerfile

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FROM ubuntu AS builder
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ADD minimdnsd.c /minimdnsd.c
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RUN apt update -y && apt install -y build-essential && gcc /minimdnsd.c -o /minimdnsd -static -Wall -pedantic -Os -g -flto -ffunction-sections -Wl,--gc-sections -fdata-sections
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FROM alpine
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COPY --from=builder /minimdnsd /minimdnsd
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ENTRYPOINT ["/minimdnsd"]

‎minimdnsd/LICENSE

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MIT License
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Copyright (c) 2024 <>< Charles Lohr
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files (the "Software"), to deal
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in the Software without restriction, including without limitation the rights
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to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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copies of the Software, and to permit persons to whom the Software is
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furnished to do so, subject to the following conditions:
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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SOFTWARE.

‎minimdnsd/Makefile

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all : minimdnsd
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PACKAGE_VERSION:=0.1-$(shell cat .github/build_number)
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PACKAGE:=minimdnsd_$(PACKAGE_VERSION)
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SHELL=/bin/bash
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CFLAGS:=-Wall -pedantic -Os -g -flto -ffunction-sections -Wl,--gc-sections -fdata-sections
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minimdnsd : minimdnsd.c
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echo $(shell expr 1 + $(shell cat .github/build_number)) > .github/build_number
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gcc -o $@ $^ $(CFLAGS)
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size $@
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install : minimdnsd
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sudo install minimdnsd /usr/local/bin/
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sudo cp minimdnsd.service /etc/systemd/system
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sudo systemctl daemon-reload
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sudo systemctl enable minimdnsd.service
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sudo service minimdnsd restart
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cat minimdnsd.1 | gzip > /usr/share/man/man1/minimdnsd.1.gz
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test : minimdnsd
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./minimdnsd &
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./minimdnsd -h testminimdnsd &
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ping -c 1 $(shell cat /etc/hostname).local # Ok, doesn't actually test anything
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killall minimdnsd
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deb : minimdnsd
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rm -rf $(PACKAGE)
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mkdir -p $(PACKAGE)/DEBIAN
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mkdir -p $(PACKAGE)/usr/bin
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cp minimdnsd $(PACKAGE)/usr/bin/
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mkdir -p $(PACKAGE)/etc/systemd/system
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cp minimdnsd $(PACKAGE)/etc/systemd/system/
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mkdir -p $(PACKAGE)/usr/share/man/man1
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cat minimdnsd.1 | gzip > $(PACKAGE)/usr/share/man/man1/minimdnsd.1.gz
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cd $(PACKAGE); find . -type f -exec md5sum {} + | cut -c 1-33,38- > DEBIAN/md5sums
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echo "Package: minimdnsd" > $(PACKAGE)/DEBIAN/control
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echo "Version: $(PACKAGE_VERSION)" >> $(PACKAGE)/DEBIAN/control
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echo "Section: base" >> $(PACKAGE)/DEBIAN/control
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echo "Priority: optional" >> $(PACKAGE)/DEBIAN/control
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echo "Architecture: $(shell dpkg --print-architecture)" >> $(PACKAGE)/DEBIAN/control
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echo "Maintainer: cnlohr <lohr85@gmail.com>" >> $(PACKAGE)/DEBIAN/control
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echo "Description: Bare bones MDNS server" >> $(PACKAGE)/DEBIAN/control
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echo "#!/bin/sh" > $(PACKAGE)/DEBIAN/postinst
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echo "set -e" >> $(PACKAGE)/DEBIAN/postinst
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echo 'case "$$1" in' >> $(PACKAGE)/DEBIAN/postinst
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echo " abort-upgrade|abort-remove|abort-deconfigure|configure)" >> $(PACKAGE)/DEBIAN/postinst
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echo " systemctl daemon-reload;systemctl enable minimdnsd.service; service minimdnsd restart" >> $(PACKAGE)/DEBIAN/postinst
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echo " ;;" >> $(PACKAGE)/DEBIAN/postinst
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echo " triggered)" >> $(PACKAGE)/DEBIAN/postinst
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echo " systemctl daemon-reload; service minimdnsd restart" >> $(PACKAGE)/DEBIAN/postinst
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echo " ;;" >> $(PACKAGE)/DEBIAN/postinst
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echo " *)" >> $(PACKAGE)/DEBIAN/postinst
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echo " ;;" >> $(PACKAGE)/DEBIAN/postinst
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echo "esac" >> $(PACKAGE)/DEBIAN/postinst
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echo "exit 0" >> $(PACKAGE)/DEBIAN/postinst
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chmod 775 $(PACKAGE)/DEBIAN/postinst
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echo "#!/bin/sh" > $(PACKAGE)/DEBIAN/prerm
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echo "set -e" >> $(PACKAGE)/DEBIAN/prerm
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echo 'case "$$1" in' >> $(PACKAGE)/DEBIAN/prerm
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echo " remove|remove-in-favour|deconfigure|deconfigure-in-favour)" >> $(PACKAGE)/DEBIAN/prerm
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echo " systemctl daemon-reload;systemctl disable minimdnsd.service; service minimdnsd stop" >> $(PACKAGE)/DEBIAN/prerm
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echo " ;;" >> $(PACKAGE)/DEBIAN/prerm
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echo " upgrade|failed-upgrade)" >> $(PACKAGE)/DEBIAN/prerm
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echo " service minimdnsd stop" >> $(PACKAGE)/DEBIAN/prerm
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echo " ;;" >> $(PACKAGE)/DEBIAN/prerm
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echo " *)" >> $(PACKAGE)/DEBIAN/prerm
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echo " ;;" >> $(PACKAGE)/DEBIAN/prerm
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echo "esac" >> $(PACKAGE)/DEBIAN/prerm
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echo "exit 0" >> $(PACKAGE)/DEBIAN/postinst
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chmod 775 $(PACKAGE)/DEBIAN/prerm
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dpkg-deb --build $(PACKAGE)
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# For manual installation override
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#mkdir -p $(PACKAGE)/etc/systemd/system/multi-user.target.wants/
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#cd $(PACKAGE)/etc/systemd/system/multi-user.target.wants && ln -s ../minimdnsd.service . || true
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clean :
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rm -rf minimdnsd minimdnsd_* -rf

‎minimdnsd/README.md

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# minimdnsd (MDNS server)
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Extremely simple MDNS server for Linux. Much smaller and lighter weight than Avahi.
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⚠️ This has not been battle hardened, or even thoroughly checked ⚠️
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Primarily MDNS Hostname responder - i.e. run this, and any computer on your network can say `ping your_hostname.local` and it will resolve to your PC. Specifically, it uses whatever name is in your `/etc/hostname`
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* Uses no CPU unless event requested.
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* Only needs around 32kB RAM.
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* Compiles to between 15-45kB
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* Can run as a user or root.
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* Zero config + Watches for `/etc/hostname` changes. (Optionally: Can use -h to also watch for a host alias)
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* Works on IPv6
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⚠️ Caveats ⚠️
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* This tool only replies to hostnames, so you can use `hostname.local` but not services, so you can't use it to find your printer.
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* This tool automatically perform both a `UNICAST-RESPONSE` and `MULTICAST-RESPONSE` - whether true or not.
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## General Motivation
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1. To obviate need for avahi-daemon
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2. To provide an MDNS server on very simple systems
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3. To act as an educational tool for the following items
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### To demonstrate the following:
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1. Use of inotify to detect changes of `/etc/hostname`
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2. Use of `getifaddrs` to iterate through all available interfaces
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3. Use of `NETLINK_ROUTE` and `RTMGRP_IPV4_IFADDR` and `RTMGRP_IPV6_IFADDR` to monitor for any new network interfaces or addresses.
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4. Use of multicast in IPv4 and IPv6 to join a multicast group
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5. Use of `recvmsg` to get the interface and address that a UDP packet is received on
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6. Use of `optarg` to handle command-line parameters.
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7. Use of `fork()` and `wait3()` to handle workers. (Only used in DNS forwarding mode)
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### And for general housekeeping:
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7. Use of github workflows to build and test tool on Linux
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8. Makefile example for building .deb files
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9. Github workflow example for generating releases on new tags.
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10. How to use/install a basic man page
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## Building
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### Prerequisits
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* build-essential (make + GCC + system headers)
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### Build process
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* `make`
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* or, optionally `make install` to install it to /usr/local/bin/minimdnsd, and install the initd service
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## Long-Term
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* Allow response to services (see original MDNS server here: https://github.com/cnlohr/esp82xx/blob/master/fwsrc/mdns.c)
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* Keep it under or around 1k LoC
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* Keep it < 32kB `.text`
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## Things I learned
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IPv6 is pain. this would have been a tiny fraction of its size if it weren't for IPv6.
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Also IPv6 with MDNS is in a really sorry state, so I was barely able to test this with IPv6.
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https://superuser.com/questions/1086954/how-do-i-use-mdns-for-ssh-6
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And ping6 has a similar issue.
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### Thanks
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For code reviews: @GPSBabelDeveloper, @probonopd
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‎minimdnsd/minimdnsd.1

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.TH MINIMDNSD 1 "June 2024" "version 0.1" "User Manuals"
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.SH "NAME"
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minimdns \- Minimal MDNS server
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.SH "SYNOPSIS"
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.B minimdnsd [-h host_alias_override] [-4] [-r]
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.SH "DESCRIPTION"
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.B minimdnsd is a minimal MDNS server, able to reply to other computers on the network at (your hostname).local
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.SH "OPTIONS"
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Usually this is intended to be used without any -h flag.
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.IP -h
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Specify a hostname override instead of using /etc/hostname - you can launch multiple instances, to get multiple overrides.
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.IP -r
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Create a dummy responder, it listens on 127.0.0.67:53 and forwards requests to 224.0.0.251:5353, but note: may or may not forward AAAA requests.
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.IP -4
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Disable IPv6 operation.
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.SH "AUTHOR"
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cnlohr <lohr85@gmail.com>
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.SH COPYRIGHT
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Copyright \(co 2024 cnlohr
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.br
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.SH LICENSE
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minimdns is licensed under the MIT-x11 license.
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