Commands by matthewbauer (52)

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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" }

Disassemble some shell code
This one liner takes the shell code that you can grab off of the web and disassemble it into readable assembly so you can validate the code does what it says, before using it. The shell code in the above example is from http://www.shell-storm.org/shellcode/files/shellcode-623.php You can replace "-s intel" with "-s att" to get AT&T format disassembly.

list files recursively by size

Number of CPU's in a system
/proc/cpuinfo contains information about the CPU. Search for "processor" in the /proc/cpuinfo file wc -l, counts the number of lines.

function to edit your history file
eh stands for Edit History . Frequently, I'll mistype a command, and then step back through my history and correct the command. As a result, both the correct and incorrect commands are in my history file. I wanted a simple way to remove the incorrect command so I don't run it by mistake. . When running this function, first the ~/bash_history file is updated, then you edit the file in vi, and then the saved history file is loaded back into memory for current usage. . while in vi, remember that `Shift-G` sends you to the bottom of the file, and `dd` removes a line. . this command is different than bash built-in `fc` because it does not run the command after editing.

find all open files by named process
lists all files that are opened by processess named $processname egrep 'w.+REG' is to filter out non file listings in lsof, awk to get the filenames, and sort | uniq to remove duplciation

Ask for a password, the passwd-style
You can ask repeatedly for a non-blank password using this function: function read_password() { while [ ! -n "$USER_PASSWORD" ]; do read -s -p"Password: " USER_PASSWORD if [ ! -n "$USER_PASSWORD" ]; then echo "ERROR: You must specify a valid password, please try again" fi echo done } Also you can set a time out (in seconds) to write the password read -t 10 -s -p"Password: " USER_PASSWORD_VARIABLE if [ ! $? -eq 0 ]; then echo "Time out!" fi

Encode/Decode text to/from Base64 on a Mac w/out Mac Ports
I have a mac, and do not want to install mac ports to get the base64 binary. Using openssl will do the trick just fine. Note, to decode base64, specify a '-d' after 'base64' in the command. Note also the files base64.decoded.txt and base64.encoded.txt are text files.

Get lines count of a list of files
This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files. The combination of print0 and files0-from options makes the whole command simple and efficient.

DVD to YouTube ready watermarked MPEG-4 AVI file using mencoder (step 2)
Reencodes to MPEG-4 DivX output video file from step 1. Audio stream is simply copied. Resizes to 320x240 and deinterlaces as needed. A heading subtitle file is applied as watermark. This heading subtitle file can be a URL.


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