Make launcher host easier to find with multiple log-in nodes
Supercomputers may have multiple log-in nodes and currently there is no way to track on which log-in node the Melissa launcher is running. This causes problems when the SSH session with the launcher call is closed (e.g., some log-in nodes terminate idle SSH connections automatically). The user may later observe that there are jobs running on the supercomputer; the user can terminate these jobs but the launcher will keep re-spawning them until the user finds the log-in node with the running Melissa launcher. This actually happened to cconrads and braffin on September 3, 2021 on Jean Zay with Deep Melissa and Code_Saturne jobs.
One idea to resolve this problem is to have each launcher write its hostname (and maybe start date, start time) to a file in the user's home directory.