Commands by kniht (5)

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Press ctrl+r in a bash shell and type a few letters of a previous command
In the sample output, I pressed ctrl+r and typed the letters las. I can't imagine how much typing this has saved me.

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" }

sort monthwise
sort command can sort month-wise (first three letters of each month). See the sample output for clarification. Sorting Stable ? NO. Take note if that matters to you. Sample output suggests that sort performs unstable sorting (see the relative order of two 'feb' entries).

Convert all .flac from a folder subtree in 192Kb mp3
find . -type f -iname '*.flac' # searches from the current folder recursively for .flac audio files | # the output (a .flac audio files with relative path from ./ ) is piped to while read FILE; do FILENAME="${FILE%.*}"; flac -cd "$FILE" | lame -b 192 - "${FILENAME}.mp3"; done # for each line on the list: # FILE gets the file with .flac extension and relative path # FILENAME gets FILE without the .flac extension # run flac for that FILE with output piped to lame conversion to mp3 using 192Kb bitrate

SMS reminder
Send an e-mail to SMS reminder in 15 minutes from now, to call my wife. See list of carriers bellow Carrier Email to SMS Gateway Alltel [10-digit phone number]@message.alltel.com AT&T (formerly Cingular) [10-digit phone number]@txt.att.net [10-digit phone number]@mms.att.net (MMS) [10-digit phone number]@cingularme.com Boost Mobile [10-digit phone number]@myboostmobile.com Nextel (now Sprint Nextel) [10-digit telephone number]@messaging.nextel.com Sprint PCS (now Sprint Nextel) [10-digit phone number]@messaging.sprintpcs.com [10-digit phone number]@pm.sprint.com (MMS) T-Mobile [10-digit phone number]@tmomail.net US Cellular [10-digit phone number]email.uscc.net (SMS) [10-digit phone number]@mms.uscc.net (MMS) Verizon [10-digit phone number]@vtext.com [10-digit phone number]@vzwpix.com (MMS) Virgin Mobile USA [10-digit phone number]@vmobl.com

List apache2 virtualhosts
Lists virtualhosts currently enabled for apache2, showing the ServerName:port, conf file and DocumentRoot

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" }

Find all active ip's in a subnet
nmap for windows and other platforms is available on developer's site: http://nmap.org/download.html nmap is robust tool with many options and has various output modes - is the best (imho) tool out there.. from nmap 5.21 man page: -oN/-oX/-oS/-oG : Output scan in normal, XML, s|

Listen to a file
replace "/usr/src/linux/kernel/signal.c" with any file you want and listen to its output ! :P you can also replace "cat" with "echo" or anything you can come up with have fun :-}

Add .gitignore files to all empty directories recursively from your current directory


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