Commands by caliburning (1)

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Count number of files in subdirectories
For each directory from the current one, list the counts of files in each of these directories. Change the -maxdepth to drill down further through directories.

formatting number with comma
it is not work with Cygwin's bash3.X. Test in Linux. use printf "%'f" number while it is floating point number

See entire packet payload using tcpdump.
This command will show you the entire payload of a packet. The final "s" increases the snaplength, grabbing the whole packet.

Renames all files in the current directory such that the new file contains no space characters.
This is a better version, as it does no command piping, uses for instead of while loops, which allows for a list of files in the current working directory to be natively processed. It also uses the -v/verbose option with mv to let you know what the command is doing. While the command does exactly the same in a better way, I would modify the sed option to replace spaces with underscores instead, or dashes. Please note that you'll receive errors with this command as it tries to rename files that don't even have spaces. This is an alternative to: http://www.commandlinefu.com/commands/view/8761/renames-all-files-in-the-current-directory-such-that-the-new-file-contains-no-space-characters.

Add thousand separator with sed, in a file or within pipe
Does not necessarily require a file to process, it can be used in a pipe as well: $ cat filename | sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta' I don't remember where I copy/pasted this from, I wish I credited the original author

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

List all duplicate directories
Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical. if in doubt apply: $ diff -rq path_to_dir1 path_to_dir2 AWK function taken from here: http://stackoverflow.com/questions/2912224/find-duplicates-lines-based-on-some-delimited-fileds-on-line

Benchmark SQL Query
Benchmark a SQL query against MySQL Server. The example runs the query 10 times, and you get the average runtime in the output. To ensure that the query does not get cached, use `RESET QUERY CACHE;` on top in the query file.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

shutdown pc in 4 hours without needing to keep terminal open / user logged in.
From the 'disown' man page: disown prevents the current shell from sending a HUP signal to each of the given jobs when the current shell terminates a login session.

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