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Linux: Running a single unique instance of command + arguments

run-one is a wrapper script that won't run the given command while another instance of it is running. Is brings several utility commands that offer similar behavior.

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NAME run-one - run just one instance at a time of some command and unique set of arguments (useful for cronjobs, eg) SYNOPSIS run-one COMMAND [ARGS] run-this-one COMMAND [ARGS] run-one-constantly COMMAND [ARGS] keep-one-running COMMAND [ARGS] run-one-until-success COMMAND [ARGS] run-one-until-failure COMMAND [ARGS] DESCRIPTION run-one is a wrapper script that runs no more than one unique instance of some command with a unique set of arguments. This is often useful with cronjobs, when you want no more than one copy running at a time. run-this-one is exactly like run-one, except that it will use pgrep(1) and kill(1) to find and kill any running processes owned by the user and matching the target commands and arguments. Note that run-this-one will block while trying to kill matching processes, until all matching processes are dead. run-one-constantly operates exactly like run-one except that it respawns "COMMAND [ARGS]" any time COMMAND exits (zero or non-zero). keep-one-running is an alias for run-one-constantly. run-one-until-success operates exactly like run-one-constantly except that it respawns "COMMAND [ARGS]" until COMMAND exits successfully (ie, exits zero). run-one-until-failure operates exactly like run-one-constantly except that it respawns "COMMAND [ARGS]" until COMMAND exits with failure (ie, exits non-zero).

Internally, it hashes command+arguments and flocks on the hash.

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Dominik Schöler
Last edit:
about 1 month ago
by Besprechungs-PC
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Posted by Dominik Schöler to makandra dev
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