2. Creating a file to indicate the run completed successfully

2.1. Problem

You want to create a persistent indicator that a run was successfully completed. One situation where this is useful is when using a workflow manager, such as Snakemake, which uses the filesystem to infer which tasks to perform.

2.2. Solution

At the end of the inputfile, use the LAMMPS built-in shell command, along with touch to create the file.

# If we get here, we are successful, so create a file to indicate that is so
shell touch done.tkn

2.3. Discussion

While NUFEB follows the unix style conventions of returning an exit code of 0 when the run completes successfully, you may also want to create some persistent indicator that the run was performed successfully. This will also ease using file-based workflows, such as make and Snakemake. To do this, we can simply tell NUFEB to create an empty file as its last instruction; in effect signalling everything else ran successfully. The name of the file can be any valid filename.

The LAMMPS shell command allows you to pass along arguments to the shell, so we can simply use touch to create the file.