Commands tagged /dev/urandom (6)

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list any Linux files without users or groups
suspicious/anomalous ownership may indicate system breach; should return no results

Which .service related this file?
I use this as an alias to get all .service files related a single installed file/conf (if it has services, of course). For rpm based systems ;)

cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

split a file by a specific number of lines
Splits the file "my_file" every 500 lines. Will create files called xx01 xx02 and so on. You can change the prefix by using the -f option. Comes in handy for splitting logfiles for example. I am using it for feeding a logfile parser with smaller files instead of one big file (due to performance reasons)

strips the first field of each line where the delimiter is the first ascii character

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

limit the cdrom driver to a specified speed
this command limit the speed to 8 until next eject of your cdrom disc , can be usefulll when you don't want to listen the sound of your cdrom driver .

Recursive search inside the content of files under current directory - then view the result paginated with 'less'
This command will traverse all of the folders and subfolders under current working directory. For every file inside it, it will do a search inside the content of the file for a specific term 'what'. Then it will print a list of the lines that contain that term (and match that pattern). Each matching line will be preceded with the path and name to the file and then the line number iside taht file wehre the pattern was found. Then the actual content of the matching lien will be printed. The output will be piped throug less, so that the user can scroll through it if it goes beyond the limits of the current display window.

Validating a file with checksum

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" }


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