tldr/pages/common/pv.md

pv

Monitor the progress of data through a pipe.

• Print the contents of the file and display a progress bar:

pv {{file}}

• Measure the speed and amount of data flow between pipes (-s is optional):

command1 | pv -s {{expected_amount_of_data_for_eta}} | command2

• Filter a file, see both progress and amount of output data:

pv -cN in {{big_text_file}} | grep {{pattern}} | pv -cN out > {{filtered_file}}

• Attach to an already running process and see its file reading progress:

pv -d {{PID}}

• Read an erroneous file, skip errors as dd conv=sync,noerror would:

pv -EE {{path_to_faulty_media}} > image.img

• Stop reading after reading specified amount of data, rate limit to 1K/s:

pv -L 1K -S {{maximum_file_size_to_be_read}}