Commands using file (166)

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Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

The simplest way to transport information over a network
Einstein's razor: As simple as possible, but not simpler. On the destination machine netcat listens on any port (1234 in the example) and sends anything it receives into a file or pipe. On the source machine a separate netcat takes input from a file or pipe and sends it over the network to the listener. This is great between machines on a LAN where you don't care about authentication, encryption, or compression and I would recommend it for being simpler than anything else in this situation. Over the internet you should use something with better security.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Mac OS X: remove extra languages to save over 3 GB of space.
This will get the job done in the most efficient way - spawning only one `rm` process. "On-the-fly" find data is displayed through `tee` and you should have plenty of time to ctrl-c if needed before it's too late. You may need to re-run this after major Software Updates. To leave more languages in, add more ``-and \! -iname "lang*"'' statements: $ sudo find / -iname "*.lproj" -and \! -iname "en*" -and \! -iname "spanish*" -print0 | tee /dev/stderr | sudo xargs -0 rm -rfv **Edit: note the 2nd sudo near the end of the pipeline - this is necessary.

randomize hostname and mac address, force dhcp renew. (for anonymous networking)
this string of commands will release your dhcp address, change your mac address, generate a new random hostname and then get a new dhcp lease.

check open ports without netstat or lsof

Copy a directory recursively without data/files

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.


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