Commands by shajeen (1)

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Create a 5 MB blank file via a seek hole
Similar to the original, but is much faster since it only needs to write the last byte as zero. A diff on testfile and testfile.seek will return that they are the same.

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" }

track flights from the command line
Usage: flight_status airline_code flight_number (optional)_offset_of_departure_date_from_today So for instance, to track a flight which departed yesterday, the optional 3rd parameter should have a value of -1. eg. flight_status ua 3655 -1 output --------- Status: Arrived Departure: San Francisco, CA (SFO) Scheduled: 6:30 AM, Jan 3 Takeoff: 7:18 AM, Jan 3 Term-Gate: Term 1 - 32A Arrival: Newark, NJ (EWR) Scheduled: 2:55 PM, Jan 3 At Gate: 3:42 PM, Jan 3 Term-Gate: Term C - C131 Note: html2text needs to be installed for this command. only tested on ubuntu 9.10

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

Change host name
With sed you can replace strings on the fly.

total text files in current dir

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by the excellent EVACopy http://evacopy.sourceforge.net

Disco lights in the terminal
Looks best in an 80x24 256-color terminal emulator.

convert ascii string to hex
just a bit simpler

check open ports without netstat or lsof


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