How do you check lsof?

There can be many files that are opened by a particular process. By using lsof -p process ID, files opened by a particular process can be checked.
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lsof command in Linux with Examples

1. FD represents as File descripter.
2. cwd : Current working directory.
3. txt : Text file.
4. mem : Memory file.
5. mmap : Memory mapped device.

What is lsof Linux command?

lsof is a command meaning “list open files”, which is used in many Unix-like systems to report a list of all open files and the processes that opened them.