Linux – How to show linux “cmp” command progress

comparisonlinuxprogress

Is there a way to show the progress when running the cmp command?

Comparing large files or partitions using cmp can take a while.

I have searched google and used man cmp, but failed to find any useful information.

With the 'dd' command for example executing

kill -USR1 [pid_of_dd]

makes dd output its status in the console.

Is there a way to make cmp do something similar?

You can use PipeViewer for this

pv firstfile | cmp -l secondfile > output

I prefer oneliners like this:

tar cf - /folder-with-big-files -P | pv -s $(du -sb /folder-with-big-files | awk '{print $1}') | gzip > big-files.tar.gz

It will have output like this:

4.69GB 0:04:50 [16.3MB/s] [==========================>        ] 78% ETA 0:01:21

For OSX (from Kenji's answer)

tar cf - /folder-with-big-files -P | pv -s $(($(du -sk /folder-with-big-files | awk '{print $1}') * 1024)) | gzip > big-files.tar.gz

Explanation:

tar tarball tool
cf create file
- use stdout instead of a file (to be able to pipe the output to the next command)
/folder-with-big-files The input folder to zip
-P use absolute paths (not necessary, see comments)

pipe to

pv progress monitor tool
-s use the following size as the total data size to transfer (for % calculation)
- $(...) evaluate the expression
- du -sb /folder-with-big-files disk usage summarize in one line with bytes. Returns eg 8367213097 folder-with-big-files
- pipe (|) to awk '{print $1}' which returns only the first part of the du output (the bytes, removing the foldername)

pipe to

objdump is part of binutils.