lsof -p process-id
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Lsof lists on its standard output file information about files opened by processes
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-p s This option excludes or selects the listing of files for the processes whose optional process IDentification (PID) numbers are in the comma-separated set s - e.g., ''123'' or ''123,^456''. (There should be no spaces in the set.) PID numbers that begin with '^' (negation) represent exclu- sions. Multiple process ID numbers are joined in a single ORed set before participating in AND option selection. However, PID exclusions are applied without ORing or ANDing and take effect before other selection criteria are applied.
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+|-r [t[m]] This option puts lsof in repeat mode. There lsof lists open files as selected by other options, delays t seconds (default fifteen), then repeats the listing, delaying and listing repetitively until stopped by a condition defined by the pre- fix to the option. If the prefix is a '-', repeat mode is endless. Lsof must be terminated with an interrupt or quit signal. If the prefix is '+', repeat mode will end the first cycle no open files are listed