lsof:tldr:24de7

The command "lsof -t ${filename}" is used to find the process ID (PID) of any files or processes that have a specific filename open.

Here's a breakdown of the command:

• "lsof" stands for "list open files". It is a command-line utility in Unix-like operating systems that lists information about files opened by processes.
• "-t" is an option for lsof that tells it to display only the process IDs (PIDs) of the matching files or processes, instead of the full details.
• "${filename}" refers to the specific filename or path you want to investigate. It can be a regular file, a directory, or a special file like a device file or a socket.
  • You need to replace "${filename}" in the command with the actual filename you want to check.

So, when you execute the command, lsof will search for any processes that have the specified filename open and display their process IDs (PIDs) as the output.