Add usage information

README.md

@@ -82,3 +82,60 @@ unit. Create a new file
 `/etc/serviced/service/git-monitor.service.d/override.conf` by typing
 `sudo systemctl edit git-monitor.service`. You can then uncomment the
 `Environment` statements, and change the value of the variables accordingly.
+
+After any changes to the configuration run:
+
+```bash
+sudo systemctl daemon-reload
+sudo systemctl restart git-montitor.service
+```
+
+### Using
+
+In order to observe your repository, you need to configure the repository list,
+and add your repository to the watchlist. To do so, edit the
+`$GITMONITOR_REPO_URLS`-file (default: `/opt/src/repository.list`). Every entry
+in the repository is a line in this file. And every line contains the local name
+of a repository and the URL to clone from in the form:
+`<myrepository>|<external URL>`. For example, a line could be:
+
+```
+PDP10Sudoku|htts://foo.bar/jali/PDP10Sudoku.git
+```
+
+Save the file. On the next poll the service performs, the repository will be
+watched. If the local repository doesn't exist yet, it is automatically cloned.
+Keep in mind that currently, the service only supports public repositories. This
+may change in the future if it is required.
+
+Now you will always have the current code on the Raspberry Pi. But it is still
+on the PI side, and not inside the simulator. To allow this, the service will
+run a shell script every time a change is detected in the system. The file must
+reside in the root directory of your repository, and be named
+`.git-monitor_after.sh`. In order to copy source code from the Raspbery Pi side
+of a PiDP 10 you can use the `mlftp` tool, and copy exactly the files you'd
+like.
+
+```bash
+#!/bin/sh
+# Copies the source files to the ITS system
+
+MLFTP="/opt/pidp10/bin/mlftp"
+
+SOURCEFILE="./src/myprogram.s"
+TARGETFILE="MYPROG 1 JALI;"
+
+
+# Functions
+log_message() {
+  local level=$1
+  local message=$2
+  timestamp=$(date +'%Y-%m-%d %H:%M:%S')
+  #echo "$timestamp [$level] $message" >> "$LOG_FILE"
+  echo "$timestamp [$level] $message"  # Also print to console (optional)
+}
+
+# Main execution
+log_message "INFO" "Uploading $SOURCEFILE to $TARGETFILE on ITS"
+$MLFTP -w its "$TARGETFILE" $SOURCEFILE
+```